The difference this year is that his backup is more intimidating to him than in the past. Lucas was never really a threat and everybody knew that. He only played well in New York, and never had a good showing anytime later. Unlike Lucas, Griese has starting experience and was brought in to compete with Fiedler rather to back him up IMO. Jay might have put up with crap in the past, but this year is the season that a worthy QB sits behind him that can and will take over if he f's up. This wasn't the case in previous years. Thats the difference.
And the fans could change a lot of things...maybe not practically, but mentally it would be devastating for any player to know that the fans he is playing for, are the same fans that would rather have his backup playing. Without fans this game would be nothing. Most players love the fans and the attention and want to be liked, that is really important for them. Just look at Takeo and the Bills. Last season when we played the Bengals our fans cheered for him everytime and supported him, cuz we knew it was gonna come down to him deciding to sign or not, and after he did, he came out publically and said that the fans made a huge difference in his decision to play in Buffalo. So in conclusion, fan influence does make a huge difference, and if you don't believe that, you're in denial.