I don't think it's that easy.
If Alfred is averaging only 2 YPC, how long can you stay with him? I've always felt that we should stay with our RB for 4 quarters, and the defense would wear down late in the game.
Then again, if that doesn't work, people will cry that we didn't make any adjustments at halftime, and that it was obvious that we weren't taking what the defense was giving.
The cause is probably a combination of things. Defenses stacking the box, blocking not being great and probably some of it on the RBs too.
But I've decided that I don't know nearly as much as Callahan or Gruden about what's really happening. And if Callahan believes that the best way to get yardage is to kick it outside with Thompson--that the inside runs just aren't working.....then I'm going to assume that he knows what he's doing.