BY DAVID THORPE

In the first-round sweep of the Heat and the seven-game struggle to oust the Nets, Bucks star Giannis Antetokounmpo looked amazing in most respects—but stubborn in trying to prove he can score from the perimeter. He made just one of 16 3s in that Heat series and eight of 31 against Brooklyn. The practice court, or December games, are a gr…