It would be tough at first but a good coach, who recruits defense well enough could adjust and shut down those offenses. Most of them do not even try, they put all their best players on offense and resources towards that style. Saban has adjusted to the spread and HUNH, by bringing in smaller, faster defenders while keeping enough talented bigger guys for the other games. If he went to Texas, he would just have to stock up more of the smaller, faster guys and just have a few of the bigger dudes, for when he did play a smashmouth team.