Whitaker completley schools Rosario and wins more less a shutout. Of course, he'd have to be wary of Rosario's power throughout and i wouldn't rule out him enjoying a brief moment of success and maybe score a KD or hurt him if Sweet Pea was to get careless at some point but even that's a long shot IMO.
Whitaker by UD, but would have to be on those P's and Q's at all times. I think Edwin had a good shot if he hadn't changed his style in his career.
Whitaker wins rather easily. He may take a good shot from Rosario but I don't think he would be in any danger against Rosario. I see Whitaker outboxing him for the majority of the fight. Remember that Whitaker also stopped Juan Nazario, who had just stopped Rosario one fight prior, and also completely outclassed Jose Luis Ramirez, who also stopped Rosario.
Not necessarily, don't forget Roger Mayweather decked Whitaker at LW and he didn't hit as hard as Rosario. But as i said above i think it's rather unlikely.
Camacho and Davis gave Rosario tons of problems and those two were skilled but primarily athleticism-based fighters. Pea was more athletic IMO than both and certainly more skilled than either. Pea also finished the fight vs Tito whilst having a broken jaw from round 6 onwards. His chin holds up to anyone not named Tommy Hearns IMO. Pea wide UD, but Rosario may have a few moments.
The Mayweather fight was early in Whitakers career. Whitaker was also hit very cleanly with a solid shot while he was clearly unfocused.