It took a while this season for Edwards-Helaire to get going, during which time the competition was not nearly as stiff as what UGA's defense will be. We have yet to see what LSU's offense looks like against an elite defense when CEH can't get yards on the ground. Granted, that's less important than previous years because LSU is philosophically pass-first at the moment, but still, it's worth watching. They still reach nearly 50/50 on run/pass ratio, skewed just a little bit to about 53% pass plays. UGA has allowed one rushing TD this year, which is insane.
The A&M game looked more like what I expected from the defense although I thought they'd score more than 7. I suspect this was a matter of LSU being more suited to stop A&M's pro-style attack than it was a matter of LSU suddenly remembering how to play defense. So, if LSU makes the playoffs, I wouldn't expect that level of performance to continue, but it could bode well vs. UGA, who runs a vaguely similar offense to the Aggies.
The book on the Tiger defense this year was a weird one. On paper it stood to be the best LSU defense in several years, but it never materialized. They put up a lot of good stats, comp% allowed, ypc catch allowed, ypcarry allowed (2nd half of Ole Miss notwithstanding*) were pretty well where you'd want them and what you'd expect from a top 10ish defense, but the pass rush was never there (A&M notwithstanding) and despite how good they were at getting teams to 3rd and long, they were not good enough at getting off the field on 3rd and long.
Guess we'll see. AU had an interesting plan for thwarting LSU's offense and they got away with it because their DL "won" rushes in the interior gaps with just 3 or 4 down linemen. Not sure how UGA's DL compares to AU's....Florida also did something somewhat similar (though not exactly) and it didn't work as well without Derrick Brown in the middle. But overall UGA should be the best defense LSU has seen, so I'm not sure how LSU will try to attack it or how they'll fare if UGA takes cues from previous opponents and floods the defensive backfield and dares LSU to try and run against a skeleton front. AU did pretty well with this, though LSU had several chances to break that game open and the score is not what you'd expect from the box score. Still, LSU never did play a complete game on offense where unforced errors and miscues didn't cost them drives, so that's not really something to count on.
Also, I just haven't watched many UGA games this year so I don't know. I can see the Dawgs holding LSU well below average, and I don't quite know what to expect from UGA O vs. LSU D.
*I think the Ole Miss game is a big thing that hurts LSU's defense in perception, especially that of the committee, and it definitely inflates some numbers in what was a pretty ugly half, defensively. That's fine, it happened, and there's nothing to do about it now. I don't consider it particularly repeatable though, as LSU effectively played with 10 on defense and they appear to have corrected that mistake. I thought during the game that Delpit's ankle was hurt again and that he was the primary culprit for what was happening. Sure enough, after rewatch and reading through some game-film breakdowns, Ole Miss definitely caught on to him and began running right to his spots and he was utterly useless. Zero agility or cutting ability, no acceleration, no pursuit, and very little physicality if he could make contact. I really don't know why they left him in the game, but it was as close to playing with 10 guys as I've seen. Arkansas and then A&M both tried some of the same stuff, but it didn't work well, A) because Plumlee is really fast, and B) Delpit sat the Arkansas game to heal and looked mostly back to healthy vs. A&M. Still, the lack of a pass rush has been a problem this year. It wouldn't surprise me if the defense put in another solid showing vs. Georgia, but if they reach a team like Ohio State, the offense better be able to participate in another shootout a la Texas/Florida/Bama, etc.