The scheme. The Bob Diaco scheme. The 3-4 scheme Husker fans (and certainly writers like this one) are just in the first chapter of trying to understand is a branch that extends off one of the biggest coaching trees on the hill.
Diaco's knowledge of it traces back, in his words, to "a couple of the beginning architects" of that defensive structure.
You see, Diaco gained plenty of 3-4 understanding from Al Groh, who gained understanding from Bill Parcells, whose New York Giant defenses called on it to help win two Super Bowls and frustrate even the likes of the great Bill Walsh and Joe Montana.