I still don't understand what on earth the NFL has to investigate here.
I haven't seen a rule that says a "human wall" is not permitted. The gunner gets his 6 foot safety zone. Beyond that, it's the bench. If a team wants to position people just outside the gunner's safety zone to gain an advantage, and the rules say it's ok, I'm in favor of it. It's innovative and clever and something I don't mind my team doing in the slightest.
My guess is that the NFL agrees with me here, because of the part of this article that says the league is considering issuing a memo on the subject. That's a different kettle of fish. If the league formally says that the human wall is unsporting, then that's that and we know going forward.
I'm not saying that the league shouldn't consider whether the sanction the Jets guy got was severe enough. And I'd have no problem with the league saying that what he did has no place in the game, and that a greater sanction is warranted. But I wouldn't like it to be retroactive.