User blog comment:Dan12322/Mario Franchise in Smash 4/@comment-4115159-20141230174135/@comment-6604133-20141231011128

If he were to be a palette swap of Luigi, he would have Luigi's moves, and not Dr. Mario's. I think that's what Dan is saying. But that makes no sense, because Dr. Luigi is Luigi just as Dr. Mario is Mario. If Dr. Luigi were to have Dr. Mario's moves, that would basically mean Luigi in a different suit adopts all of Mario's moves.

If this is too complicated or my wording is weird, basically, Dr. Luigi being a palette swap of Luigi makes sense. Not Dr. Luigi being a palette swap of Dr. Mario.