I think it's pretty unlikely that Florida would seriously pursue Capel for the job. Between the salary they'll pay and the trackrecord of success Billy has had there, like Texas, my guess is they will not have much difficulty hiring one of the hot-named coaches right now. Archie Miller would seem like an obvious choice (in view of an elite 8 and sweet 16 at Dayton + what his brother has done to date), but I think UF could make a credible run at a number of guys, including Greg Marshall, Larry Krystkowiak, Ben Jacobson, etc.
The problem I have with this entire Capel discussion is that we're artificially limiting ourselves to Duke alumni -- which, IMO, is a little bizarre considering that (i) we don't have a clear, home-run internal hire (i.e., there's no Roy Williams-type figure out there with 4 final fours and a decade-long trackrecord of dominating the Big 12), and (ii) no other aspect of the university would operate in this manner. When Duke hires a university president, it hires the best person available. Same with CEO of hospital. Same with the various deans. Same with when they hired Coach K. While ties to Duke are nice, they're hardly a key factor in making any kind of major. Duke b-ball is way too valuable an asset to just hand over the reigns to someone b/c you liked them as a player, and think they're good as an assistant.
And, towards that point, as impressed as I've been with Capel's recruiting and think he's clearly been a good assistant, the reality is that no program comparable to Duke (e.g., UNC, UK, MSU, UCLA, KU, IU) would even have Capel on the short list for their head job, let alone hire him. In that context, it seems weird to say he's the clear heir apparent. I genuinely hope that's not the case -- b/c that's not how this type of decision should be made. And, what's surprising about this entire discussion is that it ignores the fact that UNC has already shown us what can happen if you just give out the job to someone out of loyalty or a vague notion of staying in the "family." Guthridge and Doherty set that program back a number of years, and -- oh btw -- a lot of this no-show class stuff proliferated under their reigns. Roy was in-house, but he's someone who would have been at the top of the list for any major program making a hire. That's completely different IMO.