It has to be the closest three teams have ever come to a tie for best total defense in a season; Florida tops the list at 233.08 yards allowed per game, on average. TCU is second, allowing about six inches more than the Gators. Alabama is third, allowing a full two feet and eight inches more than TCU, on average. For the record, Slohio State and Texas each allow about 30 yards more than the three leaders.
Flabama still has to play itself in the SEC title game, perhaps breaking the logjam at the top.
[update: Florida got routed by Alabama, giving up 490 yards in the title game, and now averages 252.8 yards per game this season. Alabama gave up 335 yards, and now averages 241.7 yards per game. Texas now averages just over 251, good for about third place, behind #1 TCU and #2 Alabama. TCU has a decent shot at a second consecutive #1 finish in total defense.]