I realize that trying to run the ball up the middle shows confidence in the OL but, in general, running plays towards the middle of the field with a short field means having to face more defenders in order to score. And I think it is over-rated, particularly in college where OLs are not as dominant. And it seems to fail quite often, unless the OL is dominant.
What I see succeeding quite often are plays that get the ball out onto the perimeter. Even running plays out on the perimeter can work.
There has to be an understanding that it is different at the goal line because the defense only has a few yards to defend. So, while normally it might make sense to run the ball up the middle in a short yardage situation, that just is not the case at the goal line.
What I have observed is that misdirection or play action is the best at the goal line because it gets the defense to over-pursue in one direction, leaving a lane open to score on the other side.
I would run a receiver in motion, and then throw it to him on the perimeter behind the LOS, then he can lateral it to a trailing back and then block for the back so the back can score or he can throw it to another receiver. Or you have the QB fake a handoff in the middle and run a keeper around the edge to score. If there is pursuit, find the TE right in front of you and throw it. The point is that the carrier should always have a second option to throw should the path be blocked. So, run/pass options, play action fakes and misdirections using players in motion are the plays I would run most often at the goal line.
While these plays involve slightly more coordination and execution, they are not beyond the scope of normal play calling and, from what I've observed, have a much higher rate of success, all other things being equal.
I am not trying to second guess Cal and the coaching. I am just stating what I have observed in general and I'm curious what others have observed.