Originally Posted by
Medic Zero
That's one of my pet peeves too. I've got a nice mirror, I can see cars approaching from behind, and as I'm approaching an intersection with multiple lanes, if they put on their turn signal I can pick the lane that isn't in their way. So often they choose to not signal, I assume they think because I'm on a bike I can't see them so they don't bother, but it's their loss, because they get stuck behind me when they needn't be. It irks my desire for efficiency though.
In fairness, a good number of cyclists are hard to predict. It's very hard to know if a cyclist sees your turn signal.
I have taught cycling in traffic, and I teach a technique of doing two head-turns in a row. It is not to see behind you. It is to signal to drivers that you see them as well as to draw their attention to your presence. I try to remember to do this when I have a mirror, but I sometimes forget. I find I am treated very courteously when I do lots and lots of head turns. Try it!