I was listening to a Canes podcast last week (wasn't one from this site) and one of the callers to the podcast was a former Canes player with an interesting perspective. Said Shannon was the best DC Miami ever had. As a HC he got zero support from the administration in terms of a budget for staff or facilities. He won some big games but would lose relatively easy games.
In a lot of ways 2019 Diaz is 2007 Randy Shannon. 2006 Miami went 7-6 with offense minded coach (Coker). 2007 Shannon went 5-7.
2018 Miami went 7-6 with offense minded coach (Richt). 2019 Diaz will probably go 5-7.
If it plays out the same then it will be:
2019 5-7
2020 7-6
2021 9-4
2022 7-5
If Blake James is still around, I'm sure he will feel vindicated after a 9-4 season and give Diaz another 3 year deal (I'm not kidding). Then after 7-5, Miami has to buy out his contract and Miami goes after a Matt Campbell type (Al Golden pt 2). Rinse and repeat. The cycle starts anew.
Miami has had a few successes at hiring HCs.
One of Miami's best coaching hires was to get a innovative offensive coach from WSU. Fans were up in arms- if he was so good, why was he at a backwater school like Washington State? Gimmick offense. Throws too much. Ground game wins championships . He hadn't won anything. Erickson turned out pretty good. I think Leach could also be successful, with Shannon as his Sonny Lubick.
The other good hire was Mark Richt. I still think Miami could have done better (Herman was available) but Richt steadied a floundering program. That said, he had been fired for massively underachieving and could never get UGA over the hump. There is another former SEC coach, who did get his team over the hump and has a national championship, and would have an affordable salary. He has a big buyout, but I assume Miami could negotiate the buyout. Les Miles. He was damaged goods because he was behind the curve on offense. Now he believes in spread offenses. I would put him #1 on my list to stop the bleeding and give Miami instant credibility.