Essentially the Bills played steady and with the exception of the clock management by McCoach, they played a relatively mistake free game.
Denver, almost inexplicably, did all the things you noted and handed the game to the Bills on a silver platter. But also to the Bills credit, they gladly accepted every offer of the game and made Denver pay dearly every time they made their huge mistakes.
The Bills are still a 8 win team to me. They played well on Sunday but not well enough to change my opinion on that.
If they beat Atlanta away, well that is another matter indeed, As I can't believe the falcons will give the game away at home. The Bills will need to be more than steady this week.