Actually, the relatively talentless Miami D in 2016 finished 19th in defensive DVOA, the 2017 Broncos D finished 10th, and the 2018 Denver D finished 5th. The common ingredient in these rankings is talent and the lack thereof, which - to repeat myself - is something we fans factor in way too infrequently when assessing coaches. Statistically, the Bills offense was better in 2017 than 2018, but no one in their right mind would argue that Dennison did a better job than Daboll.