Originally Posted by
50PlusCycling
I can tell by the sound when a vehicle is coming up behind me, if it is going faster or slower, and how far to the side it is (the closer a car gets to the side of the the road, the more debris its tires hit).
This approach may not detect an extended side mirror as may be found on school buses and trucks.
The "Rides of Silence" program was started as a response to Larry Schwartz getting decapitated by the mirror of a school bus (
STORY).
No one knows if he had a rear-view mirror, but it's possible that he didn't and couldn't hear the extra wide mirror.