It's a win-win
Either he dominates at Texas, the Big 12 is then regarded by the media as equal if not better than the SEC, windfall results in higher pre-season rankings for other Big 12 teams, which then lets Big 12 teams populate the rankings even if they lose a couple (SEC effect)
He doesn't dominate at Texas and every time we beat him the media gets all up on our nuts because we beat the all and powerful Saban.