I have bought into the theory that Shanahan is waiting for Torain to be the every down back. By mixing Young, Hall, and Pittman into the game Shanahan is depriving any of them the opportunity to thrive and stand out from the pack, which will make it a smooth transition to Torain. In other words, lets say for example that Shanahan gave Hall 20-25 carries a game right now. There is no doubt he would get 100 yards per game and put up great stats (because any RB can run behind that line). But if Shanahan did that then how would he justify switching to Torain in week 8 or 9? Shanahan has already chosen Torain to be his full time RB and all the rat is doing is preventing any conflict for when he finally becomes healthy and ready to play.