Fisher made the right decision in sticking with Davis in the first place, he was hot and he gave us the best chance to win. Now that Davis has cooled down and has started seeing ghosts, missing wide open receivers, turning the ball over in high pressure situations, a move to Hill isn't a bad idea. Hill has the veteran experience that Davis just doesn't have, and he won't turn the ball over when the game is on the line.
I think losing Quick and J. Long really didn't help Davis' development though. If they were still in, maybe it's a different story.