The only team I consistently root for is the Packers. All because they are the NFC equivalent of the Bills (small market, not due to the rings).
But on a week to week basis, I root against the team that hurts the Bills the most in the standings.
Edit - I always root against the Cowboys
Bad for him . Hard runner.
There is a case to be made to not over -use a RB no matter how good he is.
Imo, even the McCaffery injury is due to Shanahan over using him last season.
His demeanour is certainly most annoying. And I really don't see evidence of him being a good HC. The most recent example is the terrible mis management of the clock prior to the half against us. I was surprised (and pleasantly so) when their approach was so lackadaisical at that point of the game, down by a lot.
He is a better OC than HC, my bet is he is fired after this season.
Your title says secret sauce but then this part really isn't a sauce.
Imo, the two main reasons are consistently strong defense by Spagnuolo and clutch plays by Mahomes.
The money he has, with the guaranteed part, is plenty for several families and generations. Now his health should be his and his family's priority.
Nice kid, decent QB but it's now very clear he can't stay away from injuries.