I don't think Belichick has lost as many assistants to other teams that McVay has and what's more... Belichick's assistants don't seem to fare very well once they leave the Patriots organization. That doesn't seem to be the case for coaches/assistants who have moved on from McVay and the Rams. I'm certainly in no position to effectively assess or judge, but from what I can tell, seems to me that most of the coaches and assistants from the McVay tree are doing well elsewhere.

The only one I would say has not done well isn't even coaching in the NFL anymore. He's a college coach now and he's definitely not doing well there.

Jedd Fisch was a Senior Offensive Asst. with the Rams in 2017 & 2018. In 2019 he was promoted to Asst. Offensive Coordinator. After the 2019 season Fisch left for the QB Coach job with the New England Patriots. That only lasted one season. For the past two seasons, Fisch has been the Head Coach at the Univ of Arizona where his current record is 2-12.

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