I think he has the raw skills to eventually be a good NFL HC. Taking a losing program and turning them into a championship caliber team in Texas is no small feat. Coaching HS football and coaching in the NFL are two very different animals, especially when the owner of the team is Jerry Jones.
From what I can tell, Jason has only ever been a HC. No experience as a position coach, no experience as a coordinator, only three years as a HS head coach. We tried the coach in training experiment with Garrett, and even he had some time with Saban under his belt. That experiment set us back a decade. Bringing in Witten to take over for McCarthy, with the shape this team is in, I just don't see how it works. I'm all about going for it on 4th, but this feels like a Hail Mary from our own goal line with Rowdy as the lone receiver.
Witten would be better off progressing through the college ranks, learning from experience, and eventually making his way up to the NFL. If he were a proven power 5 coordinator, I'd be all for it, But three seasons as a HC at a Texas private school coaching his kids, that's a heck of a reach.