You do not check to see if the cars are capable of stopping for you—you assume that the cars will keep going straight at their current speed.
Hmm, I feel like there are actually two different modes? In one of them, yes, you assume the car will continue on at its current speed, and you start walking expecting to pass ahead or behind it. On the other hand, when there’s enough traffic that you would have to wait indefinitely with that method (and there’s no light etc) there’s a mode where you stare at the car and start walking out, and then they slow down to let you cross. You do this with enough leeway that if they don’t see you (or are a jerk) you still have time to stop before you would get run down?
Hmm, I feel like there are actually two different modes? In one of them, yes, you assume the car will continue on at its current speed, and you start walking expecting to pass ahead or behind it. On the other hand, when there’s enough traffic that you would have to wait indefinitely with that method (and there’s no light etc) there’s a mode where you stare at the car and start walking out, and then they slow down to let you cross. You do this with enough leeway that if they don’t see you (or are a jerk) you still have time to stop before you would get run down?