I think he's battled more injuries than the fans know about. As far as the best RB, that depended on the day. The committee at SC has taken turns being the best. The OL at SC has been the biggest problem. It's hard for any RB to shine when the holes are few and far between.
He's had his moments, and has certainly looked like he was about to break out. I'm hopeful he can put it all together at BYU, cause all the physical tools are certainly there. That alone is fairly rare at BYU.