Trsnrtr

It's been explained/taught in cycling safety classes for years and years that you can't dodge a vehicle approaching from behind.

Not even with a Varia, mirror or whatever. John Forester told us that in his book, Effective Cycling. IIRC. the Varia is good for ~500' and a car approaching at 60 mph is doing 88 FPS, so that means that you'd have to be aware of the Varia beep or by sight, look over your shoulder or check mirror, take diversionary tactics, all in 5.7 seconds or less and that's assuming the car doesn't do a last second sideways maneuver. Sorry, ain't gonna happen.

That's my A&S rant for the day.

BTW, I was hit a few weeks ago by a truck's mirror on a 55 mph road. I have a Varia and I was aware of a car approaching from behind. Didn't help.