This is the best explanation anyone can offer to those people who say don't plant yourself in the left lane and cruise along. If I'm in the the left lane going 10 over the limit and I've already left a safe following distance between me and the car in front of me, I didn't leave that space for other drivers to weave into. I already assessed the situation and no matter what you think or want, that whole pile of vehicles in front of both of us (aka traffic volume) isn't going to get out of the way or move any faster for you than it did for me. Let's all just stay put in the lane we're in and we'll all get to our destinations safely.