I don't think there's any question that Riley's approach has been blessed by Shawn. Riley has made exactly zero desparate moves to "win now" and not build the right way, either by trying to import a whole slew of JUCO's or just burning shirts for the hell of it.
Really two things are at play, this is Riley's last rodeo and he's got 40 some years of coaching cash he's sitting on, so no matter how froggy some of the NU fan base wants to be with his employment, he probably don't give a fart in terms of impacting the way he runs his program. And two, behind closed doors, SE has probably given him the assurance that he'll receive some top cover even if the fan base gets froggy in the early years. I think clearly next year is going to be an indicator of how well this can go, if alot of his guys (mainly the QB and OL) start bombing, there's not going to be a lot of positive vibe about the way ahead.
One thing I appreciate about Riley is that he's embraced all that Nebraska tradition is and is also not just sitting on his pile of cash and checking out. He's making changes to try and make this thing work, both for himself and for the entire fanbase. In the end, if it doesn't work, it doesn't work, he'll retire or get fired, but he can go out with his best foot forward.