Our DL (when they're not slanting/stunting) play vertical. They get up-field and aren't concerned with gap responsibility.
Sometimes it works for a TFL, but here lies the problem.
Many times our DL run themselves out of the play and/or allow O-linemen to reach our Linebackers far too easily.
On outside zone running plays the OL simply lets our DL run upfield, they work to the 2nd level and get a body on our LB's, and often times there's a nice cut-back lane.
You can't ask your LB's to defeat blocks every play and make tackles. We will never see a Linebacker with a high number of tackles in this defense. It's not a Linebacker friendly scheme.
I'm sure D-linemen love it though, which may help with DL recruiting.
Truth be told, right now we don't even have the ideal DL to run this scheme IMO. Most of our DT's aren't athletic enough. Some of them get into the backfield and can't make the tackle. (Miller is an example, kid can't change direction to save his life. Stout at the point of attack though)
I'll show you the issue in a drawing.
Here the offense is running Outsize Zone/Stretch.
I drew the 3-technique getting reached and running through the backdoor. Now, he's likely never gonna make this play, but look how it allows the Guard to move on to the LB.
If that 3-tech stays in the B-gap, he protects the Linebacker, and the Linebacker can likely shoot through the moving A-gap.
In this case, since the 3-technique took himself out of the B-gap, the Guard is gonna move to the 2nd level and cut-off the LB.
In this play the RB would either hit the outside for a nice gain or cut inside of the DE, depending on how the blocks played out.
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