Wade Phillips, Super Bowl 50 champion and Defensive Coordinator of the Denver Broncos, is one of the most respected defensive coaches in the history of the game. This 2014 video discusses how to align players in the 3-4, what assignment they're expected to undertake, what technique they should...
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Great video I love this kind of stuff!
Wade asked his DL to know the play call and be hyper aggressive at the point of attack. In his mind it was because having players play 'read and react' was putting too much on their plate. He lines up and runs some cool stunts and gets the athletes in positions to get to the passer. Look at Bruce Matthews and JJ Watt for example; Wade moved those guys into mismatches and allowed their phenomenal skill to be maximized.
Romeo Crennel asks his DL to play 2 gap; occupy space and blockers and have stud LBs that go and make the tackles, while the OLB does the majority of the pass rushing - he still asks the DL to pass rush, but their first obligation is to stopping the run. What I love about Crennels system is that he will go amoeba front when he has a guy that can walk up and down the line of scrimmage picking the gap he wants to shoot. Remember what JD used to do - he'd walk the line then last second line up in the A and wreck shop. He needs those BIG, hulking bodies on the DL to tie up the space. Its why Jernigan made sense, IF HEALTHY, the guy would be prototypical for this system as a DE opposite Watt, not sharing snaps with Dunn.
I'll be curious to see what tweaks; if any; Weaver is going to make. Hopefully he doesnt have Mike Vrabel type growing pains as a DC because he's not gifted with the requisite talent to overcome bad play calling. Fingers crossed. He might be a lamb Pharaoh Chin might throw into the fire at the end of the year.
edit: duh - Bruce Smith. I almost corrected with Bruce Willis! This quarantine is kicking my ass!