You do realize that fumbles, int's, bad plays, bad calls and injuries are part of the game right? Do you think the Bills were the only teams who had bad OC's?
Trent wasn't the only terrible QB, Roscoe and Leodis aren't the only players who fumble and Butler and Wood weren't the only players who were injured.
Those things are all part of the game and the bills benefited from other teams misfortunes as well.
Using your logic, maybe if the Bills opponents didn't make those same mistakes last year the Bills would have won 3 games last year.