True.Caucus's favor extreme people, as Damo has said before. That's why Paul always did so well in caucus. He couldn't even begin to match it in a real primary though.
However, saying that his showing wasn't amazing is in denial. When RP was getting sometimes in the 15%, even if it is at a caucus, it is a better showing than ever for people with libertarian ideals. They aren't going away, they like it.