This is why I take up 1 lane of traffic when commuting to work. The speed limit is 30 mph. I usually average around 25 mph. I always think, if I can stay within 5 mph of the speed limit, then I have the right to take up a whole lane! If I can't keep up, or I have to slow down, then I get over to the right. I feel much safer because any cars wanting to pass me will have to be in the other lane, instead of the same one that I am in!