I realize that when there isn't a bike lane filtering up to the front of the line at a traffic light is frowned upon by some straightlace cyclists. However, what would you do if the traffic is backed up half of a mile? Which one of you would not filter in this case? It would take 20-30 minutes to cross the intersection if you don't filter. However, it would only take 5 minutes if you do.
I have to struggle with this dilema everyday. Because of extensive road construction, the traffic backup occurs daily, for the foreseeable future. I'll been honked at every other day by crazy motorists, who are probably mad because I was looking very smug as I rode straight to the front of the line. This is really the only route to take; other routes are worse. It's beginning to bother me because today this motorist also went berserk as he drove past; I can see his head bobbing and turning violently back and forth and his hand waving about. It also might have something to do with my retaliation after his honking by intentionally moving over to the middle of the lane.
edit: Just to clarify a bit, the berserk motorist honked after I had passed the intersection when traffic was flowing smoothly. I think he is pissed off that he just waited 30 minutes at the light and had to wait some more for me (the road was very narrow, and he was driving a wide body BMW SUV that wasn't going to be able to squeeze thru without killing me.)