Defensive Driving principle - do you agree?

[Helmet Head]

NOTE: There is no right or wrong answer - it's clearly a matter of opinion.


Do you agree with the following statement?
With rare exceptions, in all crashes even the driver involved who clearly did nothing blatantly wrong could have avoided the crash had he or she been following the rules of the road and defensive driving best practices such as Road Trip America's 70 Rules to Live By (http://www.roadtripamerica.com/DefensiveDriving/Drive-Safe-With-Uncle-Bob.htm) and those taught in the CA DMV curriculum (http://www.dmv.ca.gov/vehindustry/ol/drvedcur.htm).Clarifying definitions:rare exceptions: You believe fewer than one in 100 drivers will encounter such an exception in their lifetimes.

blatantly wrong: doing something like running a red light or stop sign, swerving into oncoming traffic, slamming into the back of traffic stopped at a red light, opening a car door without looking first, etc.

[Helmet Head]

This is from another thread:


@HH: speaking from years of experience teaching people how to drive and not kill themselves or others, you are pretty much right on regarding defensive driving practices.

Given sgtsmile's vote of "agree" in this poll, I just wanted to note for the record that a driving instructor has said this.

[sgtsmile]

Well, ex-driving instructor anyways ;p

My big thing is what is safe vs what is legal.

What is legal is always legal, and what is illegal is always illegal.

Legal and safe dont always match though.

I used to remind people that it is very possible to be dead right....

[genec]

Define "safe speed limits" per defensive driving.

[sgtsmile]

Speed limit = a law usually, unless someone is taking a different meaning.

What is a safe speed is determined by conditions more often than not.

I will cut and paste a previous post of mine which shows what I mean by that:

(and I quote myself, even though that is egotistical....) Thing about speed and what is safe or not vs what is legal or not is that it depends on conditions. What is legal or not is like a switch - it is on or off. It is legal or illegal. What is safe, well, that is more like a dimmer switch: there are many variables.

For example, it is perfectly safe to bomb down the 401 in Ontario around London at 140kmph IF the traffic is light and the weather conditions are good and your car can handle it. It is totally illegal to do so though, the limit is 100kmph. If it is the middle of January, and there is a blizzard blowing, it is still perfectly legal to do 100kmph even though it is mindblowingly stupid to do so. Then, 100 is NOT safe.

By the same token, it is perfectly legal to do 50kmph on residential streets in Ontario (unless otherwise signed) but in MANY cases, that is too fast and a driver to be SAFE needs to slow down.

Automatically assuming the limit is safe is false. A person can be driving dangerously (as in, going to fast - I am not talking about other dangerous behaviours) well below the limit, and be safe well above it. It depends on what the conditions are (and conditions include everything from kind of car, kind of driver, proximity of other traffic - including bikes, peds, parked cars, and other moving vehicles -, how tired a person is, sun angle, time of day, direction of travel, and so on and so on.) Conditions however have nothing to do with how legal a behaviour is. That is determined by your law makers. If you don't like the law, vote in a different law maker or take your chances. This also applies to anyone on a bike or walking as well. Dont come whining here with your "unjust" ticket you got on your bike when your behaviour is just as illegal as a car driver's is even if your running a stop sign is "safe" in your eyes. Safe in that case is not the issue, the law is. (and now I stop!!)

[pj7]

So, you are asking if I agree that in more than 90% of all vehicle incidents that the driver who did nothing obviously stupid, the said driver could have avoided the incident had they been following the rules outlined in the links above?
I "could" agree that the accident "could" have been avoided. I also would agree with someone if they were to ask me if I "could" be wrong that there is no god.
But if a person were forced to follow all of these "rules" to a T then driving would be so impractical that they would either abandon the rules or abandon the car.
I actually took time to read the links provided and think they provide nothing more than common sense and should not be called "rules" at all.

[Helmet Head]

So, you are asking if I agree that in more than 90% of all vehicle incidents that the driver who did nothing obviously stupid, the said driver could have avoided the incident had they been following the rules outlined in the links above?
I "could" agree that the accident "could" have been avoided. I also would agree with someone if they were to ask me if I "could" be wrong that there is no god.
But if a person were forced to follow all of these "rules" to a T then driving would be so impractical that they would either abandon the rules or abandon the car.
I actually took time to read the links provided and think they provide nothing more than common sense and should not be called "rules" at all.
For some people like Pete Fagerlin (see the recent "speeding" thread) avoiding stuff like side-by-side driving in adjacent lanes (at same speed, without one passing the other), waiting 4 seconds after the light turns green before entering (especially if sight lines are obscured, especially if turning left), etc., is not common sense.

[Helmet Head]

Speed limit = a law usually, unless someone is taking a different meaning.

What is a safe speed is determined by conditions more often than not.

I will cut and paste a previous post of mine which shows what I mean by that:

(and I quote myself, even though that is egotistical....) Thing about speed and what is safe or not vs what is legal or not is that it depends on conditions. What is legal or not is like a switch - it is on or off. It is legal or illegal. What is safe, well, that is more like a dimmer switch: there are many variables.

For example, it is perfectly safe to bomb down the 401 in Ontario around London at 140kmph IF the traffic is light and the weather conditions are good and your car can handle it. It is totally illegal to do so though, the limit is 100kmph. If it is the middle of January, and there is a blizzard blowing, it is still perfectly legal to do 100kmph even though it is mindblowingly stupid to do so. Then, 100 is NOT safe.

By the same token, it is perfectly legal to do 50kmph on residential streets in Ontario (unless otherwise signed) but in MANY cases, that is too fast and a driver to be SAFE needs to slow down.

Automatically assuming the limit is safe is false. A person can be driving dangerously (as in, going to fast - I am not talking about other dangerous behaviours) well below the limit, and be safe well above it. It depends on what the conditions are (and conditions include everything from kind of car, kind of driver, proximity of other traffic - including bikes, peds, parked cars, and other moving vehicles -, how tired a person is, sun angle, time of day, direction of travel, and so on and so on.) Conditions however have nothing to do with how legal a behaviour is. That is determined by your law makers. If you don't like the law, vote in a different law maker or take your chances. This also applies to anyone on a bike or walking as well. Dont come whining here with your "unjust" ticket you got on your bike when your behaviour is just as illegal as a car driver's is even if your running a stop sign is "safe" in your eyes. Safe in that case is not the issue, the law is. (and now I stop!!):love:

Gene, print this out and post it on your wall.

[pj7]

For some people like Pete Fagerlin (see the recent "speeding" thread) avoiding stuff like side-by-side driving in adjacent lanes (at same speed, without one passing the other), waiting 4 seconds after the light turns green before entering (especially if sight lines are obscured, especially if turning left), etc., is not common sense.
heh
I have not read that thread, but I can see myself agreeing with you. I believe that a drivers license is dealt out to too many people that should not have that responsibility in the first place. I am not referring to the person in your post however, since I do not know them. but I have friends and coworkers that make me cringe when I hear their "this idiot driver this morning" stories. And the real "idiot" in the story is NOT the anonymous driver either.

[Helmet Head]

heh
but I have friends and coworkers that make me cringe when I hear their "this idiot driver this morning" stories. And the real "idiot" in the story is NOT the anonymous driver either.
Exactly. Your words indicate an attitude of one who believes that almost all crashes and even close-calls can be avoided by following the rules and being vigilant (which of course is implied by "following the rules" - which is impossible to do if you're not vigilant).

[pj7]

Exactly. Your words indicate an attitude of one who believes that almost all crashes and even close-calls can be avoided by following the rules and being vigilant (which of course is implied by "following the rules" - which is impossible to do if you're not vigilant).
I do believe that a majority of incidents WOULD be avoided if people just used common sense. And the information in the links provided were just that, common sense.
As far as a majority... I'm on the fence about it because there is a broad spectum to keep in mind there. If you were to say "a majority of vehicle incidents in the US as a whole" then of course I would agree. But demographics really do play a part in it.

[zeytoun]

Ghetto Cruiser had 4 such accidents. HH agreed that they could not have been avoided.
http://bikeforums.net/showthread.php?p=3804905#post3804905

I had 1. I was rear-ended after being at a stop for 20 seconds.

[Helmet Head]

I do believe that a majority of incidents WOULD be avoided if people just used common sense. And the information in the links provided were just that, common sense.
As far as a majority... I'm on the fence about it because there is a broad spectum to keep in mind there. If you were to say "a majority of vehicle incidents in the US as a whole" then of course I would agree. But demographics really do play a part in it.
Are you suggesting in some parts of the U.S. it is highly unliklely for a defensive driver to be able to avoid being in an unavoidable crash in his lifetime? Or what?

[Helmet Head]

Ghetto Cruiser had 4 such accidents. HH agreed that they could not have been avoided.
http://bikeforums.net/showthread.php?p=3804905#post3804905

I had 1. I was rear-ended after being at a stop for 20 seconds. HH also said:

Still, just like somebody is bound to win the lottery, somebody is bound to be involved in a handful of highly unlikely crashes in his life.
Let's say 1 in 100 will encounter an unavoidable situation while driving per lifetime.
Let's say the average person drives 50 years of his lifetime. That means the odds of such an encounter are 1 in 100*50 or 1 in 5,000 per year.

I'm a little rusty with probabilities. But given the odds of 1 event per year is 1 in 5,000, what are the odds of encountering 4 events in 50 years? Regardless of what it is, it's not 0, and it's probably more than 1 in 2 billion, the approximate number of drivers on Earth.

So it's not surprising that some drivers, like GC, have had 4 such events.

[pj7]

Are you suggesting in some parts of the U.S. it is highly unliklely for a defensive driver to be able to avoid being in an unavoidable crash in his lifetime? Or what?

I'm saying that in sum areas that no matter how defensively you are while driving that there might be a better chance of you having an incident than not. Since I have not been all over the world, or the US for that matter, I just do not know so I leave that part open.
For instance, and this is just purely pulled out of my butt here.
Say Kentucky has 100 car incident/accidents per year. Now let's say that 25 of them are caused by freak rockslides coming off the highwalls and 25 of them are caused by the ground giving way due to underground springs or mines. That 50 incidents. Now let's say that 25 are caused by ignorant driver error, 10 are caused by deer and 15 are caused by weather.
Sure, defensive driving would help avoid all driver ignorance incidents, and likely most of the deer and weather ones as well. It might even help avoid a few of the mother nature ones as well if all the circumstances were right, but those types are unpredictable and mostly unavoidable.

This is what I mean by not having the information to make a statement meaning that a "majority" are avoidable, given demographics.

I will say this though, as a whole, in the United States, a majority of multi car incidents would be avoided if people just followed the laws.

[sbhikes]

I disagree. You lost me at the first qualifier.

[pj7]

I disagree. You lost me at the first qualifier.
Yeah, I had to read it 4 or 5 times myself. Reads sort of like a leagal document.
Check my re-definition of it in my first post, it's more commonly worded there ;)

[zeytoun]

Your lifetime odds of dying by means of uninentional^ accident are 1 in 34*
Your lifetime odds of dying by means of auto collision are 1 in 84.
Seven times as many are injured each year then killed. So your lifetime odds of being injured in an auto collision are 1 in 12.
There are over twice as many reported accidents, without injury, each year. So your lifetime odds of being in any auto accident is about 1 in 6.
One third of accidents are rear endings.# So you have a 1 in 18 lifetime chance of being rear-ended.

What percentage of the rear-endings do you imagine were avoidable by the person that was rear-ended? Now I can't find any specific technique to avoid rear-endings in the defensive driving guidelines you linked to. But this could include scenarios in which the car in front played a contributing factor somehow. Let's say that 3/4ths of these rear-endings could have been avoided by following these defensive driving guidelines, that would still be a lifetime average of 1 in 72.

FURTHERMORE.... this does not factor in the fact that only 2/3 of the population is licensed, or the possibility that some of the non-rear-ending accidents could have been unavoidable on the part of the not-at-fault party.

-----
^Granted, the definition of "unintentional" does not mean "unavoidable".
However, keep in mind that when statistics say that 90% of these collisions are avoidable, they don't necessarily mean avoidable by the not-at-fault party...

*http://www.nsc.org/lrs/statinfo/odds.htm

#http://www.ntsb.gov/publictn/2001/SIR0101.htm
These are stats for the U.S.

[Dchiefransom]

waiting 4 seconds after the light turns green before entering

This will cause as many accidents as it avoids. I've seen two so far this year.

[AlmostTrick]

This will cause as many accidents as it avoids. I've seen two so far this year.

Please explain.

[pj7]

Please explain.
I myself have seen this before.
Everyone is in such a damned hurry they are looking at the light and not the light in front of them. when the light turns green, the motorists up front, usually the first 3 or so, begin moving. If the first car in line is waiting 4 seconds and the others are not paying attention then BOOM, a collision.

[Helmet Head]

Your lifetime odds of dying by means of uninentional^ accident are 1 in 34*
Your lifetime odds of dying by means of auto collision are 1 in 84.
Seven times as many are injured each year then killed. So your lifetime odds of being injured in an auto collision are 1 in 12.
There are over twice as many reported accidents, without injury, each year. So your lifetime odds of being in any auto accident is about 1 in 6.
One third of accidents are rear endings.# So you have a 1 in 18 lifetime chance of being rear-ended.

What percentage of the rear-endings do you imagine were avoidable by the person that was rear-ended? Now I can't find any specific technique to avoid rear-endings in the defensive driving guidelines you linked to. But this could include scenarios in which the car in front played a contributing factor somehow. Let's say that 3/4ths of these rear-endings could have been avoided by following these defensive driving guidelines, that would still be a lifetime average of 1 in 72.

FURTHERMORE.... this does not factor in the fact that only 2/3 of the population is licensed, or the possibility that some of the non-rear-ending accidents could have been unavoidable on the part of the not-at-fault party.

-----
^Granted, the definition of "unintentional" does not mean "unavoidable".
However, keep in mind that when statistics say that 90% of these collisions are avoidable, they don't necessarily mean avoidable by the not-at-fault party...

*http://www.nsc.org/lrs/statinfo/odds.htm

#http://www.ntsb.gov/publictn/2001/SIR0101.htm
These are stats for the U.S. "So your lifetime odds of being in any auto accident is about 1 in 6." That includes being a passenger, cyclist or pedestrian, not just being a driver of an automobile, much less being a defensive driver of an automobile.

Given that the vast majority of drivers are not defensive drivers, and that most people, including defensive drivers, travel hundreds of thousands of miles as passengers of cars that are not driven by defensive drivers, this is not surprising.

Even if you were using statistics about drivers, it would be about drivers in general, not drivers that are defensive.

So while someone's odds of being in an auto collision in their lifetime may be 1 in 6, the odds of a someone being in an auto collision while driving are much lower than that. How much lower? Well, we'd have to factor out the percentage of miles one travels in an auto as a passenger rather than a driver. Is that half of the average person miles? 3/4? 1/4? 1/10? 9/10? I'm not sure. But we know all of your miles up to age 16 or so are as a passenger. Plus any travel where a friend, spouse, taxi driver, or family member is driving. Let's say 1/4 of an average person's lifetime time/miles traveling in a car are as a driver. Then you have to factor out being involved in an auto collision where you're a cyclist or pedestrian. Another 1/2? We're at 1 in 48 and we're still talking about average drivers. The odds of a defensive driver being in an auto collision while he is driving are certainly much, much lower than that. Say it's only one order of magnitude lower, or 1 in 480. If one third of those are rear-enders, that means the odds of a defensive driver being in a rear-ender in his lifetime are 1 in 1,440. Sounds about right.

[pj7]

"So your lifetime odds of being in any auto accident is about 1 in 6." That includes being a passenger, cyclist or pedestrian, not just being a driver of an automobile, much less being a defensive driver of an automobile.
I'll accept this



Given that the vast majority of drivers are not defensive drivers, and that most people, including defensive drivers, travel hundreds of thousands of miles as passengers of cars that are not driven by defensive drivers, this is not surprising.

I agree. But we do not have any proof that most drivers ARE NOT defensive drivers. In fact, a majority of drivers very well could be.


Even if you were using statistics about drivers, it would be about drivers in general, not drivers that are defensive.

Once again, I agree.


So while someone's odds of being in an auto collision in their lifetime may be 1 in 6, the odds of a someone being in an auto collision while driving are much lower than that. How much lower? Well, we'd have to factor out the percentage of miles one travels in an auto as a passenger rather than a driver. Is that half of the average person miles? 3/4? 1/4? 1/10? 9/10? I'm not sure. But we know all of your miles up to age 16 or so are as a passenger. Plus any travel where a friend, spouse, taxi driver, or family member is driving. Let's say 1/4 of an average person's lifetime time/miles traveling in a car are as a driver. Then you have to factor out being involved in an auto collision where you're a cyclist or pedestrian. Another 1/2? We're at 1 in 48 and we're still talking about average drivers. The odds of a defensive driver being in an auto collision while he is driving are certainly much, much lower than that. Say it's only one order of magnitude lower, or 1 in 480. If one third of those are rear-enders, that means the odds of a defensive driver being in a rear-ender in his lifetime are 1 in 1,440. Sounds about right.
But then this is all just speculation, right?
The actual number could me much higher or much lower.
I'm just providing some clarity here.

[AlmostTrick]

I myself have seen this before.
Everyone is in such a damned hurry they are looking at the light and not the light in front of them. when the light turns green, the motorists up front, usually the first 3 or so, begin moving. If the first car in line is waiting 4 seconds and the others are not paying attention then BOOM, a collision.

If unable to determine that the intersection is safe to enter (no possibility of red light running cross traffic that you can't see) it would be better to risk the above low impact collision than take a 45 mph t-bone. More often the impatient motorists will just honk.

[ghettocruiser]

As I also mentioned in that previous thread, I have also witnessed dozens of accidents (not the aftermath, the accident) where one of the drivers had no chance to avoid a collision, usually because they were stopped in traffic and a vehicle came from behind (or occasionally some other random direction) and hit them.

To suggest that these motorists could done something to avoid being hit (like accelerating through a red light or pulling onto the lawn of an adjacent business) had they been watching diligently and "left more room" conveys a misunderstanding of the physics of motor vehicle accidents and human and vehicle response times.

I do not believe I an the exception. I am, rather, the rule.

Minor accidents in cars are common and mundane to the point that unless there is a cracked bumper, many people do not even remember them after a few months or so. However, I think most of these same accidents could cause very serious injuries to a cyclist.

So no, not rare.

[Dchiefransom]

If unable to determine that the intersection is safe to enter (no possibility of red light running cross traffic that you can't see) it would be better to risk the above low impact collision than take a 45 mph t-bone. More often the impatient motorists will just honk.

Yes, but the two I saw did not really involve cross traffic, the drivers just hesitated for a long time. If there is no cross traffic, or all the cross lanes have already come to a stop, then why wait 4 seconds?

[pj7]

If unable to determine that the intersection is safe to enter (no possibility of red light running cross traffic that you can't see) it would be better to risk the above low impact collision than take a 45 mph t-bone. More often the impatient motorists will just honk.
Agreed.
But I was just answering a question that was openly posed, a question in which I had an answer to.

[pj7]

As I also mentioned in that previous thread, I have also witnessed dozens of accidents (not the aftermath, the accident) where one of the drivers had no chance to avoid a collision, usually because they were stopped in traffic and a vehicle came from behind (or occasionally some other random direction) and hit them.

To suggest that these motorists could done something to avoid being hit (like accelerating through a red light or pulling onto the lawn of an adjacent business) had they been watching diligently and "left more room" conveys a misunderstanding of the physics of motor vehicle accidents and human and vehicle response times.

I do not believe I an the exception. I am, rather, the rule.

Minor accidents in cars are common and mundane to the point that unless there is a cracked bumper, many people do not even remember them after a few months or so. However, I think most of these same accidents could cause very serious injuries to a cyclist.

So no, not rare.
The funny thing is, pulling on to the lawn of an adjacent business is an accident in and of itself. Or an "incident", which I like to call them. Around here it is a possible civil infraction.
So to avoid one incident, one must purposely cause another. The less of two evils I suppose. :D

[Helmet Head]

I agree. But we do not have any proof that most drivers ARE NOT defensive drivers. In fact, a majority of drivers very well could be.
Review the DD rules. Observe drivers. How many drive like that? What percentage waits 4 seconds before proceeding on a green if there is any kind of sight line issue? What percentage slows down when approaching intersections? What percentage looks right when they turn right on green (one of Gene's favorites)? What percentage stops at red lights/stop signs such that "when you look out over your hood, you see either the painted stop line on the pavement in front of you, or if you are behind another vehicle, you can see its rear tires touching the pavement." What percentage avoids side-by-side driving (Peter F, supposedly a driver instructor, claims it's impossible - yet I remember learning to avoid side-by-side driving in driver training in the mid 70s, and have been doing it religiously for 30 years)? What percentage of drivers do ALL of that habitually? I'd be genuinely surprised if it was more than 1%. Wouldn't you?



The odds of a defensive driver being in an auto collision while he is driving are certainly much, much lower than that. Say it's only one order of magnitude lower, or 1 in 480. If one third of those are rear-enders, that means the odds of a defensive driver being in a rear-ender in his lifetime are 1 in 1,440. Sounds about right.

But then this is all just speculation, right?
The actual number could me much higher or much lower.
I'm just providing some clarity here.
I suppose using observations based on empirical knowledge gained by experience isn't firm evidence, so, yes, it's speculation.

But I think it (the denominator) is much more likely to be much higher (than 480) than any lower.

[zeytoun]

. The odds of a defensive driver being in an auto collision while he is driving are certainly much, much lower than that. Say it's only one order of magnitude lower, or 1 in 480.
Sounds about right.
As usual, your logic is completely flawed.
You cannot use the odds of being a defensive driver as a factor in calculating the probability. That's retarded. That's called "Begging the Question" (see Wikipedia if your confused as to why)

[pj7]

Review the DD rules. Observe drivers. How many drive like that? What percentage waits 4 seconds before proceeding on a green if there is any kind of sight line issue? What percentage slows down when approaching intersections? What percentage looks right when they turn right on green (one of Gene's favorites)? What percentage stops at red lights/stop signs such that "when you look out over your hood, you see either the painted stop line on the pavement in front of you, or if you are behind another vehicle, you can see its rear tires touching the pavement." What percentage avoids side-by-side driving (Peter F, supposedly a driver instructor, claims it's impossible - yet I remember learning to avoid side-by-side driving in driver training in the mid 70s, and have been doing it religiously for 30 years)? What percentage of drivers do ALL of that habitually? I'd be genuinely surprised if it was more than 1%. Wouldn't you?
Oh yes, I do agree, and have stated unoquivocally that I do agree with you on this. I was just making a clarification statement. In fact, I'd say that there is NOT A SINGLE person out there who is a 100% defensive driver. Even the authors of the information yourself are likely guilty of not performing every single task that they have outlined from time to time, and possibly on a daily basis.
But I have observed people doing many of these things on my daily commute. I'm just not going to assume that they are or are not defensive drivers. We are all guilty of something. ;)


I suppose using observations based on empirical knowledge gained by experience isn't firm evidence, so, yes, it's speculation.

We both knew it was, and was not in any way trying to say that you were stating it as fact. Your post was rather clear on that matter.
My post was more for the benefit of others who might have missed your point.


But I think it (the denominator) is much more likely to be much higher (than 480) than any lower.
True, this is possible. since we are just speculating here, I'd also say it is much much much more likely to be higher.

[zeytoun]

So while someone's odds of being in an auto collision in their lifetime may be 1 in 6, the odds of a someone being in an auto collision while driving are much lower than that. How much lower? Well, we'd have to factor out the percentage of miles one travels in an auto as a passenger rather than a driver. Is that half of the average person miles? 3/4? 1/4? 1/10? 9/10? I'm not sure. But we know all of your miles up to age 16 or so are as a passenger. Plus any travel where a friend, spouse, taxi driver, or family member is driving. Let's say 1/4 of an average person's lifetime time/miles traveling in a car are as a driver. Then you have to factor out being involved in an auto collision where you're a cyclist or pedestrian. Another 1/2? We're at 1 in 48 and we're still talking about average drivers. The odds of a defensive driver being in an auto collision while he is driving are certainly much, much lower than that. Say it's only one order of magnitude lower, or 1 in 480. If one third of those are rear-enders, that means the odds of a defensive driver being in a rear-ender in his lifetime are 1 in 1,440. Sounds about right.

I was going to argue probabilities with you, until I saw this.

I don't mean any offense by this, but you're not rusty on probabilities. I don't think you ever knew how they worked.

Please, I don't mean this as an insult, I just mean that your post demonstrates a lack of understanding of the basic ideas of classical probability theory, and I am much too tired to begin to tackle this tonight.

It doesn't mean you're dumb - most people, even smart people like you, doctors, lawyers, have been totally wrong about probabilities.

But you're WAAAAY off...

[Helmet Head]

Why, are you calling me a liar Mr. Head? If you're not calling me a liar, why would you include "supposedly"? Please clarify and provide the requested Headspeak™ definitions if needed.


You need to learn to read, Mr. Head. Here is what I wrote:

simply impossible much of the time which is not the same as "it's impossible." Please focus on the "much of the time" qualifier.

Here you are again in a "semantics" discussion again due to your massive reading comprehension issues. You have a chip on your shoulder. I may be responsible for putting it there, but there it is. I can't take it back. At any rate, you are far too argumentative for me to be able to engage in intelligent discourse with you. I look forward to intelligent discussions in the future with you, when you cool off and manage to get rid of that chip on your shoulder. For now, I'm putting you on ignore, so please do not expect any replies from me. When you're ready, and if you're interested, PM me.

[Helmet Head]

As usual, your logic is completely flawed.
You cannot use the odds of being a defensive driver as a factor in calculating the probability. That's retarded. That's called "Begging the Question" (see Wikipedia if your confused as to why)
You're going to have to finish that sentence... You cannot use the odds of being a defensive driver as a factor in calculating the probability... of what?

[Helmet Head]

Yes, but the two I saw did not really involve cross traffic, the drivers just hesitated for a long time. If there is no cross traffic, or all the cross lanes have already come to a stop, then why wait 4 seconds? I agree. I would only wait if there is some issue with sight lines.

[pj7]

ROTFLMAO! You're confusing a "chip on my shoulder" with an extremely enlarged funny bone (due to your posts).

It's too bad that you're too cowardly to answer my question about the driving instructor/lying bit. It really speaks volumes about your lack of a spine.

Yes, put me on ignore and RUN AWAY! (insert Monty Python's Search for the Holy Grail scene here).

Wait a second though, what is the Headspeak* definition of "ignore"?

Maybe he wasn't calling you a liar, though it does seem that way. I know for one than when I tell people online that I program robots with lasers attached to them their BSOmeter goes buzzing. Though the fact is, I program large robots with high powered class 4 lasers attached to them.

[AlmostTrick]

As I also mentioned in that previous thread, I have also witnessed dozens of accidents (not the aftermath, the accident) where one of the drivers had no chance to avoid a collision, usually because they were stopped in traffic and a vehicle came from behind (or occasionally some other random direction) and hit them.

To suggest that these motorists could done something to avoid being hit (like accelerating through a red light or pulling onto the lawn of an adjacent business) had they been watching diligently and "left more room" conveys a misunderstanding of the physics of motor vehicle accidents and human and vehicle response times.

One thing a motorist can do is minimize the amount of time that they spend in this "sitting duck" position, while also increasing the chances of having a vehicle safely stopped behind them.

When approaching a red light start your slowing process much sooner by coasting. Any vehicle immediately behind you will be forced to gradually slow with you, or pass. Vehicles farther behind will catch up as you slow. By the time you are almost stopped, there is a better chance that the vehicle behind you is already there, and has slowed to your speed. By slowing down sooner, sometimes you won't even have to come to a complete stop before the light turns green. The less time you spend as a sitting duck (without a car safely stopped behind you) the less likely it is that you'll be rear ended, or hit from another direction while your movement options are limited.

If ones intent is to not let any other driver get ahead of them, (seems like the prevalent mindset) doing the above is not possible.

[zeytoun]

You're going to have to finish that sentence... You cannot use the odds of being a defensive driver as a factor in calculating the probability... of what? The probability of an unavoidable accident...
The reason that it is retarded in determining the probability of an unavoidable accident is because there is no clean comparison between being a defensive driver, and avoiding an accident. A non-defensive driver can very easily find themselves in an unavoidable accident. Consider two cars stopped at separate red lights, each in between two lanes of traffic. One is a defensive driver, the other is not. A car is about to rear-end each. Does the defensive driver fare differently then the non-defensive dirver?

So while someone's odds of being in an auto collision in their lifetime may be 1 in 6, the odds of a someone being in an auto collision while driving are much lower than that. Unfounded assumption.
Here's some data that you might not of considered. This probability includes people who never drove, or rode in a vehicle, like dead babies, many new yorkers, etc. The majority or miles/hours/trips in the US are passengerless. As a way of demonstrating this independently, why do you imagine there would be a carpool lane if this weren't the case.

Finally, your definition of rare is arbitrary. Think about this: Between 33-40% of accidents are rear-endings. One third of those involved the car in front being TOTALLY STOPPED* In other words, between 10-12% of accidents involve one driver rear-ending another that was completely stopped.

Unavoidable accidents don't seem so rare when you look at it from that angle.

*http://www.volpe.dot.gov/infosrc/journal/spring99/crashav.html

[Helmet Head]

The probability of an unavoidable accident...
Oh! I get it now. I see the validity in your original numbers, and the errors in mine.

Thanks for taking the time to explain.

That understood, let's go back to #18:


Your lifetime odds of dying by means of uninentional^ accident are 1 in 34*
Your lifetime odds of dying by means of auto collision are 1 in 84.
Seven times as many are injured each year then killed. So your lifetime odds of being injured in an auto collision are 1 in 12.
There are over twice as many reported accidents, without injury, each year. So your lifetime odds of being in any auto accident is about 1 in 6.
One third of accidents are rear endings.# So you have a 1 in 18 lifetime chance of being rear-ended.

What percentage of the rear-endings do you imagine were avoidable by the person that was rear-ended? Now I can't find any specific technique to avoid rear-endings in the defensive driving guidelines you linked to. But this could include scenarios in which the car in front played a contributing factor somehow. Let's say that 3/4ths of these rear-endings could have been avoided by following these defensive driving guidelines, that would still be a lifetime average of 1 in 72.

FURTHERMORE.... this does not factor in the fact that only 2/3 of the population is licensed, or the possibility that some of the non-rear-ending accidents could have been unavoidable on the part of the not-at-fault party.

Okay, so you conclude the odds of the average person being in an unavoidable rear-ender is about 1 in 72. You say it doesn't take into account that only 2/3 are licensed (implying the odds are actually lower), but it also doesn't take into account that it includes being involved in a rear-ender whether you were driving or not, does it not? It also includes those who are causing the rear-ender, as well as their passengers. For example, if 10,000 people are involved in a rear-ender per year, and say the average car has 2 people, that means only 2500 were drivers involved in an unavoidable rear-ender, no? Yet it's the hypothetical 10,000 number that drives the "so you have a 1 in 18 lifetime chance of being rear-ended" estimate from which the 1 in 72 is derived, is it not?

So let's rewind...

So the average person has a 1 in 18 lifetime chance of being involved (a driver or passenger in either car) in a rear-ender.

Assuming the average car has 2 persons, that means the average person has a 1 in 72 lifetime chance of being rear-ended while driving a car.

If we still say (admittedly generous on your part) that 3/4ths of these rear-endings could have been avoided by following these defensive driving guidelines, that would be a lifetime average chance of being a driver unavoidably rear-ended is 1 in 288.

Although, one who drives is much more likely to be a driver rear-ended than one who doesn't drive, so we do have to factor that in somehow. Plus some of those other types of collisions that are also unavoidable would drive this down, but still...

So the lifetime probability of driving and being in a crash that only the other could avoid, might not be quite as low as 1/200, but I don't think it's that far off.

Unless I'm still missing something (and I'm sure you'll tell me).

[SingingSabre]

Most of my friends have been in at least one rear-end collision which was not their fault.

Ergo I do not find it to be an exception.

Therefore I disagree with your conclusion of safe driving.

[ghettocruiser]

One thing a motorist can do is minimize the amount of time that they spend in this "sitting duck" position, while also increasing the chances of having a vehicle safely stopped behind them.

Although I mostly agree with this reasoning, it is pretty difficult to do this, as you describe it, in practice. Generally when I start slowing for a red up ahead, the motorist behind me, not looking as far up the road perhaps, will pass and pull in front of me, meaning I then have to brake faster anyways. (This effect is even more emphasized on a bike, where I never want to sprint up to a red light)

And I have to disagree that having a vehicle stopped behind you increases safety... I think you'd need several. Generally the car behind me will stop only a few feet from my back bumper... if they are in turn hit from behind, I'm still in the chain reaction no matter how much space I left in front.

[John E]

My younger son has been involved in one auto collision, as a passenger. The vehicle he occupied was rear-ended at a stoplight.

As a motorist, I have been involved in two collisions, fortunately both minor. In the first, my car, while stopped at a 2-way stop sign, was struck in the right-front corner by a wrong-way bicyclist. In the second, my car was rear-ended while I was waiting for a red light.

As a motorist, my wife has been involved in one collision. As she began to accelerate in the rain from a traffic light which had just turned green, her car was rear-ended by another. The other driver claimed it was not her fault, because "I pressing on the brake pedal as hard as I could." Give me a break (or is that brake :) ?)!

As a motorist, son #1 has been involved in one collision. While driving in the #1 lane on a 6-lane freeway (SR 78, for those who know north San Diego County), my car was struck by a pickup truck which had overshot while merging from the #3 lane into the #2 lane. Fortunately, he was essentially uninjured, but my car was totalled. When I asked him whether he had been driving defensively in his "bubble," he pointed out that both vehicles had spun all the way across the freeway, ending up on the dirt shoulder, and that there had been no secondary collisions whatsoever. His defensive driving presumably reduced the severity and consequences of the collision, but I cannot honestly say that I could have avoided the collision itself, had I been driving instead of him.

Sorry, HH, I know where you are going with this thread, i.e., that bicyclists and motorists can avoid being struck by errant motorists, but my personal experience simply does not support your arguments.

[AlmostTrick]

And I have to disagree that having a vehicle stopped behind you increases safety... I think you'd need several. Generally the car behind me will stop only a few feet from my back bumper... if they are in turn hit from behind, I'm still in the chain reaction no matter how much space I left in front.

True, but being the first one hit is almost always worse than being hit later in the chain. Plus if the guy behind you does stop too close, you can still move up after he has stopped (since you stopped well short, you should have plenty of room to do this) to increase your rear buffer. Yes he can just move up again (and sometimes will) but when done slowly with good timing he may not even notice.

[zeytoun]

Unless I'm still missing something
Yes
you conclude
No, I said, "if" "would" no conclusion
say the average car has 2 people
It doesn't. 2 people in a car is minority, and gives you special carpool privileges. Read my earlier post.
Although, one who drives is much more likely to be a driver rear-ended than one who doesn't drive, so we do have to factor that in somehow.
It's nice that you realize this, but you are not going to factor this in reasonably, then you should not factor in your other assumption.

Also note, you could have a scenario in which a car rear ends a line of cars, sandwiching several of them (my accident was of this nature). This is not unusual. This would change your number.

Now back up and realize that we have made some huge assumptions. 1) that only 25% of rear endings were unavoidable. The truth is that 33% of rear endings happen when the first car is COMPLETELY STOPPED. I would say that almost all of those were unavoidable. I would also say that many of the others might be unavoidable, in fact, estimates are that 80% of rear-endings were from the rear driver not paying attention.

Keep in mind that another, very common accident, is the lange-change collision. Almost 10% of all collisions involve one car changing lanes into another car. How many of these were avoidable?

I think that it is a lot more common then you realize.

[AlmostTrick]

Although I mostly agree with this reasoning, it is pretty difficult to do this, as you describe it, in practice. Generally when I start slowing for a red up ahead, the motorist behind me, not looking as far up the road perhaps, will pass and pull in front of me, meaning I then have to brake faster anyways. (This effect is even more emphasized on a bike, where I never want to sprint up to a red light)


It works well for me but I can see how regional differences in things like distances between lights and/or amount of traffic may vary the effectiveness. I find driving like this to be second nature and less stressful. It is similar to how cyclists are forced to handle the situation because of their speed limitations, and plenty of them report cycling to be less stressful (or even less dangerous) than driving.

[deputyjones]

Although I mostly agree with this reasoning, it is pretty difficult to do this, as you describe it, in practice. Generally when I start slowing for a red up ahead, the motorist behind me, not looking as far up the road perhaps, will pass and pull in front of me, meaning I then have to brake faster anyways. (This effect is even more emphasized on a bike, where I never want to sprint up to a red light)

And I have to disagree that having a vehicle stopped behind you increases safety... I think you'd need several. Generally the car behind me will stop only a few feet from my back bumper... if they are in turn hit from behind, I'm still in the chain reaction no matter how much space I left in front.

+1, With our 45-55 MPH speed limits the chain reaction, rear-end collision involving 3-4 cars is quite common although it helps anyway to have someone behind you (preferably in a 3/4 truck :D).

I would defititely agree that 90% of accidents in general could have been avoided if either vehicle involved in the crash had recognized the problem and done something to avoid it (this percentage is much higher if you consider all the accidents that are avoided and thus not reported). In fact, just this month I avoided major 3 collisions at least one of which could have easily resulted in my death while at work:


Lady ran a light on a 55 MPH road about 15 seconds after the light turned red for her and I was crossing with the green at full speed. (I saw her coming and hit my lights and siren stopping other traffic around me as she came barrelling through with a face like this :eek: )
Another lady ran another red 10 seconds after it had turned red as I was starting up from a stop at a T intersection.
Guy passed me on the shoulder at 60 MPH, and I caught it as I checked my right mirror before making a right turn (I never even realized I did this until I avoided that crash).


Although to speak in absolutes like, "waiting 4 seconds after the light turns green" is a bit naive and ignores the fluid nature of traffic (as most of these discussions of definitions and absolutes do). I am EXTREMELY vigilant at intersections because I know from lots of experience that a light runner can cause the most serious crashes, many times fatal, but that does not mean I sit there with a watch and wait a predetermined number of seconds and then with blinders on just go through the intersection assuming that since I waited my 4 seconds everything should be golden. When I am waiting at a red light I watch traffic and the light actively and watch for traffic to begin to slow significantly before heading through. This typically results in NO waiting for me as most people slow significantly for the yellow. The only time I find myself waiting is when there is a car a few hundred yards away who is still travelling near the speed limit (this is typically those jack rabbit "why brake until I absolutely have to?" type of drivers), and at those times I find myself waiting to see that cars nose dive attempting to stop for the red.

Also, I drove a little Toyota Corolla for a while and found myself wholly unable to see the entire intersection while surrounded by SUV drivers (everybody here has a big 'ole pick 'em up truck or Suburban). In those instances when I was in the right lane with a truck or SUV in the left blocking my view I would just follow along side them as they entered the intersection. If someone blew the light to our left I might still get sideswiped by the SUV that was just t-boned, but I would easily survive.

[AlmostTrick]

Many good points there Deputy. How many miles do you put on in a year in the cruiser? It sounds like you've had plenty of experience.

[deputyjones]

Many good points there Deputy. How many miles do you put on in a year in the cruiser? It sounds like you've had plenty of experience.

O, I figure about 20,000 miles per year. I drive about 100+ miles per shift. We work 12 hours shifts and, consequently, work half the days of the year. That is all on surface streets as well. Maybe 1/2% of that is on limited-access highway.

The rate of Officer involved collisions is incredibly low even though by nature of our job we are always multi-tasking while driving (watching other cars for violations, scanning the sides of the roads and at houses and businesses for suspicious activity, reading LEIN info on our computers, talking on the radio, etc.). The difference, IMHO, is that, typically, we do not regard driving as passive activity like most people do. We are usually active and vigilant in scanning the road for hazards and trying to deal with Murphy by preparing for what someone might do and preparing some avoidance before they do it.

[sgtsmile]

And I have to disagree that having a vehicle stopped behind you increases safety... I think you'd need several. Generally the car behind me will stop only a few feet from my back bumper... if they are in turn hit from behind, I'm still in the chain reaction no matter how much space I left in front.

True, but....

If you position yourself well, you can see the person about to rear end the person behind you and move out of the way yourself. It usually takes a cushion of several cars behind you to create a big enough buffer for safety. And even then, you need room to get out of the way of the out of control guy/gal who plows into the line of cars you are in which is why the school I used to teach for suggested leaving a MINIMUM of one car length even when 4 or 5 cars were behind and they you still need to monitor the mirrors, even if you have been stopped for a while.

[RobertHurst]

Exactly. Your words indicate an attitude of one who believes that almost all crashes and even close-calls can be avoided by following the rules and being vigilant (which of course is implied by "following the rules" - which is impossible to do if you're not vigilant).


Whoa, horsey. Following the rules implies vigilance? Impossible to follow the rules if you're not vigilant? Did you mean to write that?

That is a massively incorrect statement.

Robert