in ways that others don't have. A lot of his big runs are also on plays where the intended play has broken down leaving defenders scattered all over. It's not that nobody else is capable of it. The threat of Williams also helps him. He sells fakes to Williams really well. defenses collapse and Hill gets to run free.
His speed, elusiveness, and size does help him a ton, but it's not like he can just hike the ball and take off 60 yards. He has help in one form or another. It's not like RB plays where there's no 3 or 4 second delay before you take off.