Name some Champions who had an advantage over an opponent. Then for some unexpliccable reason coasted the last few rounds.(not due to injury) maybe they got away with it. Maybe they didn't. Or do you believe a true Champion should never ease off.
Jersey Joe Walcott did that against Louis the first time, and it ended up costing him the official verdict (though most felt he won anyway).
Not a champion, but Halger did it against Vito in fight one. Rosenbloom made a career out of it. Holmes coasted against Williams
Roy jones.He could have had more kos than he has but he dint want to take risks his fight with Reggie Johnson is an example of that but theres more.
I think it was the other way around: Leonard knew he had to do something, and really poored it on while Duran seemed very tired. Leonard made the fight very close by winning those last two rounds.