Article from last month, but NFL head coaches are talking to a 35 year old guy who lives on the East Side about how to stop spread offenses in the NAIA and the NFL.
https://www.si.com/vault/2018/11/13/scheme-save-defenses
As points come in unprecedented waves, NFL defensive minds search in unexpected places with hopes of sparking the counter-revolution
RANCH-STYLE HOUSES of red and tan brick border Grand View University, nestled into a leafy neighborhood a few minutes outside Des Moines. The morning quiet is sporadically broken by alert Pomeranians sprinting through doggy doors to bark at unfamiliar faces heading to class on the campus where, upon a whiteboard inside the athletic department's facilities, you might find the dry-erase scribblings of defensive football's future.
This is three days before an October game against Peru (Neb.) State College, and Travis Johansen, the GVU Vikings' 35-year-old defensive coordinator, has his opponent's personnel groupings laid out in front of him in the form of four neat diagrams. Grand View won the NAIA title in 2013, the year Johansen arrived, and his defense has been among the nation's dozen best every full season since.
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At Grand View, Johansen's approach is rooted in simplicity. He uses a micro playbook, about two pages long, that changes each week. Instead of forcing his entire working theory upon his defense, he arms players with only a few fundamental techniques that they'll need for the upcoming game—simple maneuvers they'll rep over and over during practice.
Keeping things simple allows the defense to stay flexible. Against RPO-based teams, for example, his Vikings may appear in what looks like a dime front (six defensive backs) when, in reality, it's a balanced run D that swaps out slot corners for safeties who can assist against the ground game, like smaller linebackers. In other words: "position-less football," says Johansen, who pulls up one concept, circles his safety and notes, "he's anything from a defensive end to [a DB] playing Cover-0 in the slot."
Those linebackers and defensive backs whom offenses are trying to manipulate with RPOs? Johansen teaches each one to treat the receiver in front of him like a sparring partner in a boxing ring. And he structures his defense, at times, with just three down linemen, each with the responsibility of widening the tackle box to prevent breakaway runs. Johansen is, in his words, "reinventing the defense" every week.
https://www.si.com/vault/2018/11/13/scheme-save-defenses