Originally Posted by
wphamilton
but we can't, so inevitably there has to be some compromise.
One can compromise too much (beyond the point real understanding).
I don't have a problem with trying to perform analyses (or discussing those attempts) but some people here are
way too certain about what those analyses really mean.
Originally Posted by
wphamilton
My reasoning on the intersections (including driveways) is simply that the only difference in risk is cross traffic, including right and left hooks, so that it matters less long you're exposed in approaching and crossing, having generally the same risk for an intersection whether you're averaging 10 mph or 20 mph for example. On a per hour basis you'd assume double the risk at the lower <should this be "higher"??> average speed, which makes less sense to me than simply presuming a risk at each one and summing them. Which would scale generally with miles traveled.
Since it appears that drivers have more difficulty seeing/expecting cyclists at intersections, the intersection risk of driving at 20 mph could be less than the risk of bicycling at 10 mph. And a person might fair better in a 20 mph car collision. Anyway, cycling commuters are likely going to be riding much shorter distances on average that driving commuters.