Not necessarily directed at your post but at what point is

adding yet another game detrimental to the health and well being of the players actually involved? I think there is a point in the NFL season every year where the rookies that play hit the wall because they aren't accustomed to the even faster and more violent collisions over the course of 16 regular season games plus 4 preseason games.

I'm stating the obvious, but the teams that make the playoffs and appear in the final game play 15 games if they appear in a conference championship game. Assuming elimination of conference championship games, then it backs down to 14 games for finalists, but with an 8 team playoff the total games played goes back to 15 for the finalists. There was an 11 game regular season when I attended ND, plus a bowl if your shitbird coach didn't get you on probation. In the era of Ara and earlier there were 10 game regular seasons (9 at one point) and for a while ND didn't attend bowl games as a matter of school policy.

Setting aside those guys that end up with meaningful degrees, a 15 game season is just using these kids up and throwing them away when they aren't useful anymore--hyperbole, maybe, but not by a lot.