Strongly agreed. Our program has built itself, historically, on the strength of early-entrant talent that stayed for 3 years: Donyell, Ray, Rip, Ben, Emeka, Boone, Williams, Thabeet, Kemba. Many of these guys had the opportunity to leave even earlier, but came back to school, accomplished more with their teams, and improved their draft position. One of JC's underrated strengths was his ability to convey to his guys when it was time to leave and when it wasn't, and to get them to buy in.
Daniels and, especially, Hamilton are the only 2 I can think of where they left too early and with more to accomplish. To KO's credit, during his tenure he was able to retain Shabazz and Boat, when both could have left early. Obviously that was critical for NC #4.