I can tell you when I do it in TX, I don't hold anyone up. That's a fact. I am usually half a mile down the road before the cagers clear the intersection. They accelerate like loaded cement trucks around here, not counting the 10 seconds it takes to notice the light has turned green. And every cager needs at least a football field in front of him before he can start accelerating. Then they all get stuck at the next red light, the one I cleared on green long ago. There aren't near as many commuter bikes here as in CA, but if there is already a bike filtering I just hang back. If they want to race me off the line, well that would be real progress, we could probably get an extra 5 or 6 cars thru the intersection before it turned red again.
In CA it's like the bikes have their own lane, when they just keep filtering up to one light after another without leaving the centerline. There are always cars at the next intersection, because the light never clears all the existing cars waiting at that light, so they don't get back in a lane, they just stay in the center for miles. How does this hold you up? If I split to a light, beat everybody off the line badly, turn right down the next street, then turn in my driveway without any cars getting within 1000 yds of me, does this hold you up?
Nevertheless it works fine in CA and most of the rest of the world, it's only here in the 49 states that we have this third-grader mentality. Waaaahhhhhh, he's cutting in line.