every game is exactly that. A myth. The officials that called last year's game were Big XII officials which is typically the group that BYU uses to handle away games. On occasion I understand that you guys use MWC crews but it's typically Big XII.

As for the 5 theories in the OP:
1. Utah gets away with murder on defense? No
Our WRs are bad at getting open, thereby eliminating the need for Utah to interfere? Yes
We've had bad luck with officials? No
Our WRs are bad at selling defensive PI? Maybe
Or is PI sample size inherently too small to form conclusive theories? Maybe