I have no doubt Utah is good enough to beat TCU (and vice versa), but Utah had a couple of games they could have won, but lost. TCU had a couple of games they could have lost, but won. The system rightfully rewards consistency, not just how good a team is when playing their best ball.
But we should get to answer some of these "late season peaking" questions once the real playoffs start and the dumb system we have now goes away.