I was never quite on the same page as it seemed most were -- at least in terms of the whole idea that Bennett was thrilled to be here. By the end of the season, he seemed to be going through the motions around the team. On the field he continued to play hard, so tons of credit to him for that. I know we all appreciate it and I can speak for myself when I say that I hold no ill will whatsoever towards Bennett.
I think between the denial of the December offer, along with immediately vocalizing his giddiness about hitting the free agent market ($$$) in a postgame interview following the Super Bowl -- while on the field and still in uniform -- ultimately caused Belichick to walk away. I'm not sure when that 'walk away' happened, but I imagine that it would've been around the time he saw that interview replayed in his office.
And fwiw, I tend to think this parting was largely mutual. I get the sense that Bennett had moved on quite awhile ago and wasn't expecting, or wanting, for that matter, to be back in New England. No idea why that is, tons of variables involved...
Just my two cents on the whole situation.