Smartfootball recently re-posted this NYT profile of Mike Leach when he was at Texas Tech. I thought it was worth sharing - it's an incredibly fun read.
I don't know how successful Leach would be as an NFL head coach (he's probably too weird), but honestly him and Dave Toub would be my top candidates. Even if it didn't work out, I'd love to have Leach as a coach because at least it'd be fun.
https://www.nytimes.com/2005/12/04/magazine/coach-leach-goes-deep-very-deep.html
There's of course lots of fun stuff about pirates and how Leach goes on tirades about history or crazy stories during QB meetings but a couple other things that jumped out:
1) Not that he coined it, but Leach used the mantra of "Do Your Job!" back in 2005.
2) Michael Lewis interviews Jim Schwartz where he was interviewing for HC positions. He was interested in bring on a college coach - but NFL teams were avoiding college coaches because they had a high failure rate in the NFL.
But Schwartz's argument is that college coaches fail because teams hire big names from big schools. These coaches have huge advantages they don't in the NFL. But mid-level schools who have success outsized to their school? These are the college coaches to hire.
That still rings true today.
