of tight spaces to get free. That's a skill that is under-rated, as is the first 3 steps or number of steps to get to top speed. 40 time is obviously important, but IMO less important that those first 3 steps after stopping and / or change of direction. And, the ability to really know your speed, and be able to predict how you can get through a space that's temporarily open is a major key to a good RB. Some guys have an over-inflated concept of how fast they are, and try to get through spaces that they just aren't capable of, then fail repeatedly, even if they have top end 40 or 100 speed.