More about the scientific method employed by the debunked authority to arrive at a quantitative conclusion. Note especially the last paragraph and how the Forester's quantitative conclusion on risk comparison ("ratio of dangers") was arrived at using Forester Brand Scientific Methods.

From: John Forester <forester@j...>
Date: Wed Oct 4, 2000 5:10 pm
Subject: Re: [CG] Dangerous bike paths

Answers to two different comments.

First, the comment that comparing cycling on urban sidepaths to cycling on the roadway is like comparing motoring on the street of a city designed in medieval times with motoring on a rural highway. Sure, that would be an unfair comparison, but that was not the comparison that I made. I compared cycling on a roadway with cycling on the adjacent sidepath, because the law required that the sidepath be used instead of the roadway, ostensibly (But not actually; the truth is more complicated.) for the reason that the sidepath was safer. The comparison that I tested was between the hazard rates of using two different facilities to achieve the same transportation utility, when cyclists were required to use only the more dangerous facility (or find another, less direct, route entirely). The choice that this demonstrated was that the cyclist who chose to operate according to the law had the choice of either operating at the same speed as he had used on the roadway, at the cost of tremendous danger, or of operating at the much slower speed that would provide equal safety as the roadway had provided at much higher speed. That's the choice forced on the cyclist by the bikeway activists: normal speed or normal danger, but not both simultaneously.

Second comment. How did I evaluate the ratio of dangers. Well, I had cycled the roadway route for a year or so on my way to and from work, without, so far as I could recall, any serious hazard from motor vehicles. I never had to make an emergency maneuver to extricate myself from a collision situation. That was about 3,000 miles of travel on those roadways without any problem at all. When I made the test rides (I made two; the bike activists persuaded me that the results of my first ride were dubious, that I might have been misled. So I was a damned fool enough to give them some credence. Damned near killed me.) During those test rides, I had to take drastic emergency maneuvers to extricate myself from collision situations which, for most cyclists, would have resulted in a car-bike collision, at an average frequency of 0.7 miles. I had to do such things as swerve out into the street at full speed without looking, to avoid the car exiting the driveway, or the car crossing the stop-signed crosswalk. At one point, swerving to avoid a car I hit the curb instead of the narrow ramp, which cost me only a tire. At another, I was forced to make an emergency right turn to avoid a right hook, and ended up on the wrong side of the side street (turning radius is limited by speed, you know), and then had to dodge around a car coming the other way. The final hazard was when I tried a left turn from the sidepath of a four-lane street. I looked ahead for the ramp to descend to roadway level. I looked behind for cars coming my way. I looked ahead for cars coming the other way. Platoons of cars in each direction, but far enough away. So I concentrated on the ramp and made my turn. When I could look up again, the car coming from behind in the #1 lane was speeding, far ahead of the rest of the platoon, and would hit me. I was still leaned over for a left turn, so all that I could do was to tighten the turn onto the lane stripe between the #1 and #2 lanes, heading upstream in the wrong direction straight into that platoon of cars. Luckily, no motorist was trying to change lanes at that time, or he would have killed me. I maneuvered across that platoon and out of it across the street center line, only to find that, now, the platoon of cars from the other direction had reached and surrounded me, with their drivers probably wondering where in Hell I had sprung from. I got across that platoon the the curb and sat down to think things over. I realized that these urban bicycle-safety sidepaths were even more dangerous than I had estimated from the first ride, and realized that it was only luck, despite my bike-handling and traffic skills, that had preserved me from a likely fatal car-bike collision.

So how did I calculate a danger ratio for the two facilities? 3,000 miles with no troubles on the road, when I would have had 4,200 such horrifying encounters for the same distance on the sidepath. I think that I was conservative when I gave a ratio of only 1,000 to 1. Sure, there are plenty of vociferous, bike-safety promoting bikeway advocates who have decried the test as mere anecdote. Some have even had the arrogance to condemn me for riding so dangerously, without realizing that this demonstrates the danger of the facilities that they advocate. But note this! Not one of those safety-minded bikeway advocates has had the courage to repeat this test of the facilities that they advocate. Come on, #.#., put your body where you mouth is, repeat the test for some reasonable test distance, say 500 miles, and if you survive we might pay attention to you.
John Forester