Originally Posted by
spare_wheel
I think mirror use can be helpful in some circumstances. Nevertheless, your claim that a mirror would increase my "situational awareness" is amusing. IMO, those who argue that mirrors are always helpful simply do not have much experience riding in dense urban traffic and are extrapolating from multi-lane high speed roads with clear sight lines (eg ex-, sub- and sprawl-urban street design).
I ride on multi-lane roads and I also ride in dense urban traffic. I find a mirror helpful. You can disagree, but don't pretend to know everything. A mirror is a tool. It doesn't provide complete awareness, but it is extremely useful in many situations. If you want to just limit your riding to dense urban traffic and don't think a mirror helps you, that's your choice, but don't discount the utility of a mirror if you don't use one.