Tennessee is and always has been one of the toughest jobs in the league. Delmonico overcame it for a while with the excitement of a new facility and an aggressive brand of baseball, but the whole game has changed since he left. The new transfer rule, APR, rise of Vanderbilt's program and mandatory scholarship minimums make it more difficult.
What Thompson did at Auburn was hire a great staff. He knew the league inside and out and what was necessary to win. I think at this point an argument can be made that, despite the resume of success, CDS was the wrong hire because he had very little idea what it took to be successful in this league.