If BYU is doing so well in the 2nd quarter as you suggest, why would they adjust? The plan is to shore up some things at half time and run 2-3 series in the second half. If the other team has an answer you adjust. If they can't stop what you were doing keep doing it.

In other words, if they did tweak what was working and it stopped, you would be having an equal size heart attack that they went away from what was working. You cannot have both sides of the argument. If 2nd quarter was working, you don't make major adjustments until they stop what you were doing. (See Utah / Harvey Unga game).