Always try to be objective.
There are a lot of variables to consider, beginning with essentially, a completely new defensive staff. If they improve as a unit and coaching group, the defense could be much improved next year.
However, this is a reach, and I would be inclined to say that, no, Dooley cannot beat Saban on a regular basis, based on what I have seen. And Tennessee football will not be "back" until we can, at the very least, split games with Bama (as we know them now) over a 6 year period, IMO.
I worked for an hour on a post, analyzing Dooley, but dropped it in the end. One of the things I mentioned was how we are not "coaching up" our players. Teams like Boise State, Virginia Tech and Kansas State take 3* players and beat powerhouses stacked with 4* and 5*. If we have seen one thing in these three years, our players more or less perform to their "star ability". No one rises above their perceived potential, and some (Bray, Hunter, etc.) are continuing to make mistakes that a freshman would. The lack of growth there is a concern.
I could go on, but I know you are on the same page, so I digress.