Really...the A&M defense is as good as KSU or ND? Sumlin has never been known as a defensive coach. I don't get the faith in the A&M D. They gave up 27 to Ole Miss, 57 to La.Tech, 28 to Sam Houston St., 29 to Missouri, and even 21 to Auburn. Their defensive stats aren't those of a great D. They can score, but so can OU. It may come down to whoever has the ball last. A&M scored 45 ppg, but gave up 22 ppg this year. OU scored 40 ppg and gave up 24. Some seem to think A&M and Manziel will score at will against OU, but somehow that great Aggie defense will shutdown Landry Jones and OU...I don't see it.
I can see how just looking at what you have stated would lead you to believe that A&M's defense is second-rate. However, like so many things the devil is in the details. Here is what happened with defense in each of the games you reference:
Ole Miss: Six turnovers....not the defense's fault. You give up points when you give the other team the ball inside your thirty.
La Tech: Four defensive starters were suspended for the game due to disciplinary action from the Summer (LA Tech supposed to be our first game). A&M played only fifteen defensive players in the entire game against what is/was statistically the nation's most productive offense.
Auburn: A&M lead 49-7 in the third quarter when Sumlin pulled the starters and put in the second and third string.
Sam Houston: A&M lead 52-10 late in the third quarter when Sumlin took out the starters and put in the second and third string.
Missouri: A&M lead 47-7 late in the third quarter when Sumlin took out the starters and put in second and third string.
The "so what": A&M and others recognized coming into the conference that our biggest issue was defensive depth once you got past the first string guys. We knew/know that you can't survive for long in the SEC without defensive depth. This has been our biggest focus in a great 2013 recruiting class of high schoolers and JUCO recruits. At this time, we simply don't have the depth needed on defensive for a slug fest with the likes of BAMA, UGA, UF and LSU. Potent offense in our games in the conference helped mitigate that problem this year. However, when players were suspended and/or the defensive second stringers came in...the result was ugly as you can see from the above. Our expectation is that the first string defensive guys will not be pulled in the OU game and that defensive starters will not be suspended for that game. Now....if the offense commits five turnovers like we did against LSU....OU will score a bunch of points. Sure hoping we both win our games.