lack of 'leg drive', that is. But, and this is very much IMHO, there was another in that mold that did well. Steven Jackson. Steven was all upper body strength, seemed to me. AND... he was 'elite' in that regard. If Steven got his upper body into the tackle he was going forward. Below the waist, however, you could take him down with a feather, (exaggerating a bit).
Lets get this very clear... I loved Jackson, and think he was an all time great RB... but there were times when he would go down from the flimsiest of leg tackles I've ever seen. Sometimes it appeared 'surreal', in that a one hand glancing blow to the upper thigh wouldn't just bring him down but knock him backwards.
But all that said, I don't think Gurley actually is in that mold. Not a power runner but he can break leg tackles and will unless firmly in the grasp of the tackler. - JamesJM