Originally Posted by
parkbrav
I don't mean to put words in people's mouth, I know one cyclist (@Jim_from_Boston) on these boards attaches rear-view mirrors to his helmet, I suspect that may assist in his awareness of motorists behind him. I would be interested to know if he "acknowledges" them, I haven't heard him say anything to this effect, however.
I too have a single rear-view mirror attached to my helmet and I find that it does help with knowing what is approaching, especially when I am in traffic.