Earlier this year I talked about how making streets feel more dangerous can actually make them safer.
Thinking, Fast and Slow by Daniel Kahneman gives an explanation for why this might be. Basically, the high =-energy state of the brain is activated when danger is perceived, and this state is better at avoiding pitfalls that fool the low energy state that the brain is in most of the time. Daniel calls these system 1 (low energy) and system 2 (high energy).
Interesting to ponder: what happens when all of the streets feel dangerous? Do fewer people drive because of the stress it invokes? Do people become immune to this? Do they become fatigued? It's one thing to be in a high energy state for a few seconds at an intersection. It's quite another to be living in it for hours.