Rankings don't mean near as much to me as talent evaluation (and development which Sumlin gets credit for), Briles was one of the best and has always won with less. Levine simply wasn't a good fit. The biggest benefit Sumlin had in that final season was the number of upper classmen on the team over talent. Those men were in the program for 4 to 5 years. IT plays a huge role.
Sumlin is a good coach, I don't think he is a great coach or recruiter. Sumlin was gifted an amazing OL roster and a generational talent at QB that allowed him to beat Bama in his inaugural season and earn his best record since taking the job, he hasn't done much with his recruits and the attrition is atrocious.
I mostly agree here up to this point in his career. I think his recruiting style is to get what he perceives as they highest ranked players but is not getting the chemistry right, hence the disaster with Allen and Murray. My point in making comparisons earlier to other coaches is simply to say that the book is not finished on Sumlin. He's 8 years into his head coaching career. There are certainly warning signs and he will have to correct those to reach his potential as a head coach.