I don't think anyone really knows how good UGA's defense is. They've been good against the competition they've played but just who are they? 3 teams ranked 100th or worse in scoring offense, a 1AA team, and SC who is currently in the 80's in offense and flopping like a fish trying to find a QB that can move the team.
We know they have alot of talent but the 16 ppg allowed by UT's d against their competition doesn't compare poorly to the 7 ppg allowed by UGA against their competition.
UT's 1A opponents are averaging 31.6 ppg w/out counting their game against the Vols. UGA's 1A opponents are averaging 16 ppg without counting their games against the Dawgs. IOW's, they've played against horrible offenses.
This may be the game UGA arrives... but they've done nothing on either side of the ball to suggest they are better than UT.