I see your point but this is Miami, I mean SMU? We can just cross every one of those of the list bar Clemson, PSU and maybe Washington.
They're all listed for a reason.
-Chris Peterson had Boise undefeated in year 1 as a first time HC, and took 3 years to get Washington rolling.
-James Franklin time
@Vandy was listed to contrast his time @Penn.
-Same for Matt Rhule, because I don't know how you'd ignore what he's done at Baylor, and Temple is there to show he took 3 years both tries.
-Mark D'antonio is debatable I'll admit, but he's at the very least been to the playoffs.
-Kik Ferentz is debatable, but Iowa was terrible before he got there.
-SMU to pretty much credit Lashlee for the improvement.
-Mack Brown because UNC is in our division so its definitely relevant. Plus he has a Natty under his belt even though he never won it before Texas hired him.
-PJ Fleck @Minnesota is interesting as well, and that's in the Big 10, so nothing to scoff at.
This is to highlight how long it took a coach to have a relatively successful season. Not to compare the programs. OP suggests that we'll know enough about Diaz after year 2, but I disagree and think 2 years isn't enough(assuming they made changes) because success has taken a while for more than a few coaches.