I don't think anyone is saying the D is a gimmick. I look at it simply in terms of match-up. Given the Texas offensive style, any team that can generate pressure with four is going to give us trouble. OU and Nebraska have awesome d-lines, the kind that can get pressure with 4. Colt, given his experience, is excellent at exploiting the blitz. If Bama has to blitz to get pressure, this is a much better match-up than OU or Nebraska.
I don't understand why the Longhonrs fans have such a hard time understanding this. The defense is a 3-4 look, but more often than not, one of the LBs will either have their hand down or be close to the LOS playing like a rush end/DE. Even if that is not the case we will typically bring 4 rushers. The difference between Saban's scheme and the typical 4-3 is you cannot be certain of the identity of the fourth rusher, it could be the LB/DE hybrid, another LB, a DB, etc. That is not "blitzing" that is a standard pass rush. Blitzing is when we bring 5 rushers or more, just like with a 4-3 alignment. I just don't understand why the UT fans keep getting hung up on sacks by the 3 DL. We WILL get pressure with the front 4, we have all year against equal or better OL. The 4th rusher's stats is just spread among several players. Dareus has done about the most damage though.