I don't have these numbers, but I'm positive that the lifetime risk for having experienced a serious car accident (or any car accident for that matter) is stron

I don't have these numbers, but I'm positive that the lifetime risk for having experienced a serious car accident (or any car accident for that matter) is strongly correlated with driving behavior and specifically speeding. Second, there's the matter of just how damn uncomfortable it is to be around speeding cars when you're not also in a car yourself. People in suburbs don't really think about this because nobody walks anywhere. But I live in a walkable urban environment and the speeders here are an enormous hit to quality of life. They're louder, more aggressive -- it's just really unsettling to be around. This can be hard to convince suburbanites of, because they conceive of themselves mostly as drivers and not as pedestrians, but even if there were no safety improvements, it would be a huge win for urban environments if we could rein in speeding. But the reality is that it would also save ~6,000 lives a year in the U.S.