People keep theorizing that the game plan was to take away Heupel's strengths by limiting deep shots and making them work the field until it's compressed.
I'll push back - the game plan was "this is our defense so we're going to run it." Yes, it's a good fit to Heupel's base scheme. But Heupel hasn't really been running that scheme, and it was clear pretty fast they were going to take things slow in this game.
As time wore on and Bama needed stops and turnovers, you HAVE to adjust your defensive approach to play complementary football and get stops or turnovers. Tennessee had no need to take risks, so you aren't going to get lucky picks sitting in zone (bc they were NOT taking shots down field). Bama, at that point, needed to force Tennessee into throwing downfield, with the expectation that their QB wasn't very good at making them and might force a game-changing turnover.
But all that seems mind-bogglingly academic when the reality is I saw zero indication that Bama can run anything but their base 3-3-5 stack scheme. They aren't multiple. They can't run a 4-4 and go cover-1. They can't run a 5-2 and press man on the outside. Understanding real life isn't Madden (players can't run whatever you call no matter what without practice), you need to rep a Plan B, C, and D to succeed at a playoff level.
So, until proven otherwise, I just have to assume Bama's D can be elite when their scheme matches up against the opponent scheme and game situation. It will suck when it doesn't. And "they're going to pound the ball on us in a low scoring game until we tire late" is unfortunately a scheme/situation teams are seeing a LOT of in playoff-deciding games now.