Here's a thought. (forgive the momentary political interjection, it is used to make a point.) Kamela Harris was told by her former extramarital boyfriend Willie Brown NOT to accept the VP nomination as it was a road to nowhere politically. He said she'd never get another meaningful gig. (Seems he may be more politically savvy than Harris by a long shot.)
At what point do O and D coordinators on the rise say "No Thank You" to the Steelers because they realize Mike Tomlin (literally) has no coaching tree. As far as I know, he hasn't produced one single subordinate who's ever advanced their career elsewhere.
Stats guys? What's the situation there?