“Honestly, most people thought we played a 4-3 at the Giants. Lawrence Taylor did a lot more rushing than he did pass-dropping; probably 80-90 percent of the time he was the rusher in the defense,” Belichick said.
“It wasn’t always a pass, but certainly in passing situations and a lot of pass plays, he was the designated fourth rusher, which really put us in what amounts to a 4-3.
"Honestly, I think that’s something that is a media fabrication. There are a lot of different alignments out there. You see 4-3 teams use odd spacing. You see 3-4 teams use even spacing. You have 11 players, you can put them in various positions. Whether you want to put it on the pre-game depth chart as one thing or another, I think is a little bit overrated.
"You play different fronts, you play different spacing, and you teach the techniques of your defense. That is what consistent, techniques that are taught in different defensive systems, whether those teams go from three-man line to a four-man line, or a four-man line to an odd spacing line, or overs to unders, or unders to overs, or over-wides, whatever you want to call it. They will continue to play the same fundamental techniques as they’ve been teaching for the entire year, for the most part. I think that’s what teaching defensive fundamental football is about. It’s about fundamentals. Wherever you put them, you’ve got to people other people in complementary places, however you decide to do that.
"It’s pretty straight-forward really … It’s more the teaching, techniques and fundamentals you teach your defensive players, more than it is the 4-3, 3-4 lineup that is so important to put on the flip card.”
https://www.patspropaganda.com/honestly-most-people-thought-we-played-a-4-3-at/