In a comment to an answer about helmet replacement mention was made of a mirror and perhaps suggesting that a helmet was merely a good place to mount a mirror. I, hopefully humorously, suggested that a mirror user might not have much inside to need protection of a helmet ...
As someone who does a lot of miles and most of them in town, where seeing behind you is useful, I've never even considered a mirror. My preconception is that any mirror small enough to not be obtrusive or distracting would not be large enough to provide a decent view behind and, besides, I can look over my shoulder periodically and get a decent grasp for free.
So what am I not seeing; why should I use a mirror?
