I think it is hard to say anyone is being built up as a successor right now.
The catch 22 I always had with Pruitt being the hire was that what if he leaves us for Bama post Saban? I say this assuming that Dabo says no, Bama freaking out and making a huge offer to Kirby to try to get him to leave UGA only for him to say no.... If you're Bama and you have Pruitt has done well at Tennessee (a few SEC title game appearances, maybe a playoff berth) in 4-5 years, or whenever Saban retires, what would be better than stealing a Bama alum from your rival that is on the uppity up?
With that said if Bama is poaching our coach, that means Pruitt will have been a massive success. Regardless of the fact, I think Fulmer's final two (Pruitt and Mel Tucker) were solid candidates. My preference was Tucker just because of the Pruitt-Bama angle.
I think there is no significant reason that Pruitt would stay at Tennessee just because he built the program his way over getting a chance to go home. I won't hold that against him because if we were in the same boat to still a Tennessee Alum coaching at Bama, we'd all be stoked to do it.
Fact of the matter is that Pruitt's only shot at Bama means he has to win here and have Dabo, Kirby, and maybe someone else say no... I think his only route to Bama is winning and being the 3rd or 4th option.....
With that said, I think the combo of Pruitt and Chaney is helpful for not just Tee as you mentioned, but Ansley as well.