While it is a nice video for understanding basics of the cover 4, don't skip the important reveal at 16:30. It's mentioned multiple times Woods isn't from the Fangio tree and never worked with Fangio. Woods runs a system more aligned with the Niners and Jets because of his own coaching tree. The Browns line coach Chris Kiffin worked under Saleh.
The Browns up front run a scheme that the film maker suggests is ideal for cover 4, but they don't have the talent in the defensive interior.
The tree is kind of irrelevant - Woods runs a similar Cover-4 system to those from the Fangio tree, which is why he was included in this video. There are some differences for sure (particularly with the DB coverages... Woods coverages are a lot more vanilla), but the nature of the system is to take away the TD on every play. Bend but don't break, and hope the opposing QB makes a mistake. While the filmmaker acknowledges that the Browns interior defense is lacking in talent, it doesn't mean there aren't other problems present:
1. Soft coverage allowing everything underneath - this was great against Mahomes and Allen a couple years ago but they've since adjusted. It causes problems for guys like Kyler Murray, but is an easy defense for mid and bottom-tier QBs to pick apart. Guys who are incapable of making homerun plays all the time welcome soft enough coverage that lets them make the 8 yard completion almost every down. The filmmaker specifically mentions this.
2. Inability to communicate scheme to players will have the disastrous effect of allowing the one thing the entire scheme is meant to prevent - homerun plays. As we saw with Woods defense in the 1st half of the year, miscommunication issues and breakdowns allowed subpar/trash QBs to break the backend of our defense.
3. Lack of disguises and creativity on the defensive front - hardly any stunts and creative blitz packages gives the offense the easiest time of their lives. He specifically mentions how Brandon Staley adjusted his cover-4 scheme and was able to completely fluster Tua and the Mike McDaniel offense through a variety of stuns and off-script blitzes. He also mentions how teams like Baltimore are top 10 in cover-4 but they're unpredictable with how they use it - often switching between aggressive, press coverage and single-high along with situational blitzing.
4. Not adjusting to the opponent - the filmmaker stresses how important it is to recognize the opposing QB and know when giving them easier completions is helping their offense vs hurting it. You do this against prolific QBs (which might be why we do so well against Burrow generally, and last year caused problems for Aaron Rodgers) who can beat you quickly... you don't do it against the Flaccos, Bakers, Mariotas, Trubiskys, Zappes of the world. But Woods has shown to be inflexible not only during the game, but with his weekly gameplan.
5. Non-commitment to base defense and/or more players in the box will result in getting gashed in the run game. The NFL is averaging the most yards per run in the HISTORY of the game this year. This scheme relies on the two interior linemen to maintain multiple gaps, and then asks the LBs to shed upfield blocks and make critical one-on-one tackles. It's compounded even more with our terrible interior but schematically Woods hasn't shown any ability to adjust or try to compensate for it.
It's a great video... and I don't think it should be downplayed just because it makes Woods look terrible (not that we shouldn't already feel this way).