His Defense has allowed the Chiefs to score their lost points on every Postseason they've played. No need to cherry pick.
Josh Allen gives you a top 5 Offense. Teams know they have to score and start playing riskier which is why against average to below average teams our Defense feasts and then against elite Offenses they look lost.
As far as the the playoff breaking drought. Need you remember he benched Tyrod for Peterman in that season and won by beating exclusively bad teams. Even then it took the miracle of Andy Dalton to Boyd to backdoor into the playoffs. IMO that season was his best coaching and he has fumbled against Andy Reid in the playoffs. It's like he over thinks himself. There is 0 excuse for 13 seconds. 0
Also he's better than 2 time CotY Kevin Stefanski. Those CotY are jokes.