We learned what we already knew. Josh is the entire Bills team, offense and defense. We have invested more salary cap and draft picks on defense than any other NFL team. And we have used that investment to build a defense that works great when Allen puts incredible pressure on the other team, giving them the impression we will score on every drive. This makes the other teams play one-dimensionally and makes it easy on the offense.
Because of the investment on defense in the salary cap, we don't have the types of weapons on offense that KC or the Dophins have. If Allen falters, no one is on offense to pick up the slack.
Because the defense can only be great when defending a big lead, if Allen falters, the defense cannot reliablly control the game. Today's game ending drive was just the long drawn out painful version of 13 seconds.