To me seeing New England in regular season, Tampa, KC in super bowl and to some extent Dallas’ offensively, it should settle the coaches over players debate since 90% of fans and the media think changing out the coaches is what’s the key to winning.
Andy Reid has been dominant the last 3 years and very good his whole career minus the last few years in Philly. But he goes up against a very good D with 3 new starters on the OL and look what happens. He is much better than 9 points and so is Mahomes but when you don’t get protection it doesn’t matter.
New England most of the world including me thought Brady was made by Belichick and it doesn’t matter who Belichick had, he’d win with anyone. Well that was proven terribly wrong and even more so after Brady and Gronk go to TB and win.
Dallas offensively was going up and down the field the first 3 weeks. Take out both tackles and the starting QB and it’s not so easy anymore.
I think there’s some coaches on the high end (Reid, Belichick) and low end (Gase) of the spectrum, but probably for the most part the separation in knowledge from the best HC to the worst is pretty small. Maybe 1-2 games at most. And while motivation matters, this isn’t college. Pros should be able to motivate themselves.
There’s outliers like Adam Gase whose players get drastically better after they leave his system like Tannehill. But most HCs got their jobs because of great success as an assistant or a HC previously so they all know football. Matt Nagys plays look really good in preseason and on paper when pro bowlers aren’t going against him trying to break them up.
But going from even just an above average starter to a backup level player is a much greater leap than any coach. I’m not saying Gase or Garrett would have won 3 Super Bowls in NE during their hay day but Jimmy Johnson didn’t win any in Miami. Bruce Arians is a pretty good coach but he’s not good enough by himself to take Tampa from where they are to a Super Bowl.