to get back to the topic of the thread, I think McDermott has been reinventing himself every year. Look at the offensive philosophy change this year from pass first to run first. We have cut out turnovers in half as a result. That is a huge improvement due to coaching and scheme completely independent of bringing in better players.
The NFL has engineered the rules so much that the bully defenses of the 1985 Bears and 2000 Ravens are no longer possible. As we don't have a Maxx Crosby, Bosa brother, TJ Watt or Micah Parsons the best we can do in engineer pressure. We have beaten the best teams in the league this season. I don't much care how we win only that we win. The main risk I see on D is that our offense scores so much so quickly that our D gets gassed.
I am confident that Clappy will call the right plays at the right time to engineer a coverage sack and turnover when we need one. SO I expect him to continue to evolve as a coach like he has every year with the changes in coordinator and philosophy we have already seen.