I'm on the fence w Kiffin. I would definitely be skeptical but would reserve judgment until seeing the product on the field. If there's anyone who could whip him into shape and ensure he respects Tennessee tradition, however, I think it would be Gruden. I think Kiffin has 1) learned a lot 2) is a fantastic coach, and 3) wants to prove he can beat Saban.
I will say it appears Kiffin appears to have been trying to mend Tennessee fences, so it's not altogether implausible to think he's in play.
At the end of the day, if Gruden thinks a Kiffen OC and a Zook DC gives UT the best chance to be successful and the coaches can work together as a team, I'm all for it. I understand the hesitation, though.