Anecdotal counter-proposal: Drivers are often aware of the cyclist, but simply don't care. There have been a noticeable number of occasions, for example, where I ( the yellow-bedecked, blinky-flashing Fred we all love to hate ) have stopped at an intersection, had the right of way, made eye contact with the drivers, including ones behind me, gotten a nod in return... and had them right hook or blow in front of me. Perhaps some of them thought that even when I was in front of them, had taken the lane, and was obviously going straight, they had an intrinsic and legal right to go around me. On the left.