Paranos you can't 2 gap and be attacking. 2 gap is being responsible for two gaps and in an attacking format you take your assigned gap and disrupt.
This. If our DTs had the ability to re-establish a LOS 2-3 yards behind the backfield it would have been done. They aren't taught to sit on their heels and catch and release...that's a ridiculous assumption. Our DTs just weren't very talented.
Both of you are wrong. If you watch film of how UM's interior Dlinemen set up before the snap of the ball you will notice their weight is shifted back on thier heels and the first post snap move is a punch out with both hands in order to engage the offensive linemen an prevent them from reaching 2nd level blocks against the LB'ers. This how you control two gaps by occupying the OL while you check either side gap for the ball carrier while attempting to quickly disengage and defeat the blocker in order to give supporting inside out pursuit of the ball carrier. This is where the term reading the block then reacting comes from. Now you can teach to read and react with the goal of a getting a stalemate at the LOS which is considered a win, or you can teach read and react while pushing the blocker into the backfield to collapse the pocket from the very first movement which will result in a tackle for loss being considered a win. But when you push the LOS backward while trying to maintain gap integrity, if all your Dlinemen aren't on the same page you will open a natural whole for the ball carrier in. This is why the reestablishing the LOS 2yd in the backfield type of 2 gap scheme is only effective if you have country strong wardaddy type linemen with long arms, that both understand the defense an even more importantly are willing to play their role as glorified blockers.
An Attacking defensive dline as you mentioned picks a gap and blows throughout any way they can, an inorder to get generate as much initial burst as possible the linemen get down in a track stance with as much as possible leaning forward on their hands and their feet are in a staggered set to allow for the first step to be a burst forward using the snap of the hips to generate acceleration.
Watch any UM highlight from last year and you will see porter and renfrow setting up in almost a sumo wrestler stance, which is used to create a stalemate rather than generate a push. Where as if you watch ND, Bama, Wisconson, or FSU all whom run a 3-4 scheme that looks to reestablish a new LOS in the backfield.
Here is a highlight of Louis Nix playing NT Notice how he presses the pocket run or pass on every play to reestablish the LOS 2-3yds in the backfield. Then watch how Curtis Porter is set up to play the NT within Miami's scheme where catches the block an tries to stalemate them at the LOS but gets pushed back a yard a or so. 3 years ago porter was a wrecking crew in old attacking style defense UM. You won't find highly ranked DT's that are willing to the NT, you need more blue collar role player types an this why Bama signs only specific types of 3*'s or unradar types to play the NT. An even Bama's DT's aren't usually rated higher than a low 4* at most, because they are role players also to a certain extent. Here is a clip of Wis NT Beau Allen running the same type of scheme UM's runs except they execute it better because they have the strength across their front line TNT players to run it, this is actually what I expect UM's front 7 to look like for 2014. Hopefully this clears up your confusion.
[video=youtube;0amU0_ZaYlY]http://www.youtube.com/watch?v=0amU0_ZaYlY[/video]
[video=vimeo;86245423]http://vimeo.com/86245423[/video]
[video=youtube;SO5NLcVTh20]http://www.youtube.com/watch?v=SO5NLcVTh20[/video]