Utah is 0-3 against former Pac 12 teams and those are their 3 largest margins of defeat. Hard to say who they would have beat in the Pac. They would have struggled anywhere. Their defense is generally good enough to keep them in games, but the offense put up a combined 17 points against arizona and tcu who are 2 awful defenses. If you can't score on those teams you're not scoring on anybody regardless if it is pac 12 or big 12.