No offense to the road warriors out there, but around here the "serious cyclist" types don't do cycling in general any favors. As Ron described, they MAYBE slow down for a red light, maybe not. I have never seen one slow down for a stop sign. It's a wonder there aren't more collisions. When I mentioned the Saturday morning training rides the local racing club does, a friend nearly jumped down my throat, saying "Yeah, and they spread out over the whole #&!**?$ road so you can't get past them!"
I neglected to mention that this guy was suitably impressed when he asked how many miles I had on my bike and I told him almost 2800 since November. I think it might be more than he rides.