What makes me ill at ease is that Sark's bona fides are as a guy who coaches players. I've come to believe that, especially at a place like Texas, a head coach has to excel at the CEO stuff - having the overall vision for the direction of the organization, attracting and retaining the best staff, mentoring and managing his people and getting them what they need to succeed, handling the politics of it all. However good he is as an X's and O's coach, it's a big question mark as to whether he can do that successfully. And I worry that an X's and O's coach is at a disadvantage here if that means they're trying to micromanage things down at the player level.
Working with Saban should be a master class in keeping an organization humming, and hopefully Sark learned a lot there, but a lot of Saban assistants have gone on to less-than-illustrious careers. I also wouldn't be surprised if a guy as pathologically competitive as Saban sees all his assistants as potential future competition and doesn't go out of his way to teach them how to do his job.