Bush finding success up the middle?

One of the primary concerns about Reggie Bush as a featured back in the NFL has been the belief that he is not a reliable option between the tackles. At 6-foot, 200 pounds, he clearly isn't built to hammer the ball up the middle like a fullback. Plus, during his two seasons with the Miami Dolphins, he averaged a pedestrian 4.37 yards on 208 carries up the middle, which seemingly supported that notion further.