I said this before & here is Kyle Jones’ article about it. Both times we’ve played them in the B1G championship, they’ve brought it. We are vastly more talented but their simple and aggressive structure was tough.  Day has said multiple times that it’s tough to get yards against them. We know he thinks the Cover-1 is the toughest defense to go against but the teams that have played us the best since he’s been coach have played with 2 safeties.

Philosophically, it is the same intent to stop the run and make offenses work for yards. It seems to do more with less talent, too. Easier for guys to learn to play/not as dependent on elite talent.

https://www.google.com/amp/s/www.elevenwarriors.com/ohio-state-football/film-study/2020/12/119256/film-study-northwesterns-no-nonsense-approach-to-defense-continues-to-carry-the-program%3famp

Philosophically, Hankwitz's defense is quite similar to the one installed by Jeff Hafley last year in Columbus. The Wildcats play a four-man front with the back-seven keeping their eyes on the ball to contain big plays and force opponents to put together long drives in order to score.

How Hankwitz chooses to bring that plan to life is quite different, however. His defense operates almost exclusively with two-deep safeties, relying on zone-match Cover 4/Quarters coverage to give his defenders a chance to steal a look at the backfield (like a traditional zone defender) before playing routes more like man-coverage.