Bill Belichick might not have any hard feelings toward Josh McDaniels, who was his offensive coordinator for many successful seasons. But even if he did, he doesn't have the team to get much revenge on his old protege.
The New England Patriots aren't capable of imposing their will on anyone this season. They followed up the worst loss of Belichick's coaching career with the second-worst loss of his career. That was telling because for Belichick's career, the Patriots always seemed to rally and win after embarrassing losses.
They're just not capable of that anymore.