That might not even be A/H. But IMVHO, a divided convention of one side or the other is quite possible. If there's two candidates who each have a significant portion of the delegates--but not a majority--the delegates for other candidates have to jump in. But if a radical candidate refuses, on principle (real or imaginary) to give up his delegates, there could be a deadlock. Imagine a candidate that would rather bring down the system than give up--I can see some politicians that might think that way.
Is there a provision for that? And if the delegates refuse to vote for someon they don't like, neither can get a majority.