The following is from a thread I made at www.cowboys-forum.com. This is a video comparison between a few plays from the 2006 San Diego Chargers defense and the 2006 Dallas Cowboys defense.
If you would like to see the discussion from the original thread, click this link: CLICK HERE

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Well, there have been a lot of questions and discussions flying around about the differences between the way Wade Phillips runs his 3-4 defense and the way Parcells and Zimmer ran the 3-4 last season.

This comparison only covers the front 7 (DLine and LBs). I didn't get into the different secondary coverage schemes each coach used. Beyond the fact that Zimmer is the only coach I've ever seen that used the Cover 2 in the 3-4, I believe Wade Phillips' coverage schemes are fairly standard, although he has to suit his coverages to match his blitzing scheme.

The Phillips' 3-4 is VERY aggressive. Basically, he wants to get into the backfield and completely disrupt the offense. One thing I noticed while doing the game video editting is that all of the various blitzes that he runs (and there are A LOT of them) seem to be VERY precise and well planned. Each defensive player that is in the area of a blitz is aware of where the blitz is coming from... and they perform their assignments to try to give the blitzer the best opportunity to get a free run into the offensive backfield.

Its almost a complete opposite philosophy between these 2 defenses.
Parcells/Zimmer: "We are going to deal with what the offense throws at us"
Phillips: "I'm going to force the offense to deal with what we throw at them"
Parcells/Zimmer rarely ever made players switch sides to get favorable matchups whereas Phillips almost ALWAYS had his players switch sides to get favorable matchups.... ESPECIALLY his OLB's.

SAN DIEGO CHARGERS FILM STUDY:

Play#1 OLB Stunt
On this play there are 3 defensive players that make it happen. The OLB Shaun Phillips #95, the near side DE, and the near side ILB. The DE slants to the outside of the Tackle to draw him outside creating a gap between him and the Guard. The ILB blitzes and slants to the inside shoulder of the Guard. The OLB waits for the DE to slant outside and then chargers around him into the HUGE hole that was created by the DE's and ILB's maneuver.
Result of the play: OLB forces a terrible throw and into an interception.

Play#2 DE & NT Stunt
On this play there are 2 players involved. The DE and NT run a basic stunt of the defensiveline where the DE runs around to the inside of the NT and the NT slants to the outside. This is an attempt to create confusion on the offensive line. On this particular play, it doesn't confuse the offensive line, but it does get the Guard off balance a little when they switch players. The result of this play is a sack by the NT Jamall Williams... but he's a freaking beast and just bulled the All-Pro center into the backfield.

Play#3 ILB Blitz
On this play, there's really only 1 player that runs a different assignment than a normal pass rush. That's the ILB. I'm very excited to see this blitz ran by our Cowboys defense. The DE and OLB (Merriman) line up just as normal. The ILB steps up to the line of scrimmage almost the moment the ball is snapped to blitz. What's great about this is, he lines up between the DE and the OLB. Well this obviously overloads that side of the line to where there is almost no way they could block all of the guys rushing on that side. The Guard has to block the DE. The Tackles has to block the blitzing ILB. And the CENTER tries to jump outside to block the OLB which is a failed attempt. The OLB Merriman winds up getting the sack.

Play#4 DLine vs the Run
This play exhibits the difference between Phillips' defensive linemen and Parcells' defensive linemen. What you see here is the DE just shoot the gap and get into the backfield for a tackle for loss on the RB.
When you watch the Cowboys film breakdown, you'll see how really different it is.

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DALLAS COWBOYS FILM STUDY:

Play#1 Basic Pass Rush
On this play, you can see that we only have 4 guys rushing vs 6 blockers (until the RB Westbrook slips out into the flat). This is pretty much the level of pass rush we had on the majority of plays in the 2006 defense. Very basic, no surprises for the offensive line, and, consequently hardly any pressure on the QB.

Play#2 SS & ILB Blitz
On this play, we see Roy Williams and Bradie James blitzing. The biggest problem is that we SEE that they are going to be blitzing a good 3 seconds before the ball is snapped. Consequently, the offensive line picks them up without much trouble and the QB is able to make a throw before the pressure gets to him.

Play#3 ILB Blitz
On this play, we can see that Akin Ayodele runs some sort of a half attempted blitz up the middle. Once he engages the offensive lineman, he just kind of gives up. Jay Ratliff (the NT) makes the play on the QB but only because he makes some good moves to get by the Center. Akin is the only player that does anything special on this play. None of the dlinemen do anything to assist the blitzing ILB.

Play#4 DLine vs the Run
On this play, we can clearly see that our DLinemen are taught to engage and hold the line of scrimmage. All 3 of the dlinemen engage the offensive line and stop driving their feet. They engage, read that its a run and pretty much just stop. The problem is, our ILB's got blocked, Demarcus Ware just barely misses making the tackle, and Roy Williams has to come out of the secondary to make the tackle at the sideline. Nobody in the front 7 (besides Ware) did anything to ATTACK the offense. They all just waited for the offense to hit them and then stopped driving their feet.

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