I wouldn't say he struggles against southpaws but he is more open to hit without having to fake him like Shane did. Yes he dominated most of the southpaws in his career but they were able to hit him cleanly and last time I checked, it only takes one punch to get anyone out of there.
My God Gander doesn't know ****. What's worse is he tries to play it off like he knows what he is talking about.
If the opponent is a big puncher, yes. Mosley domination aside, if that was a Hearns hitting him with a right hand, Floyd would be 40-1 KOed 1