Sweden would be a communist country by now if any of the socdem "theories" were right. Social Democracy is pure opportunism and anyone telling you that we need to have social democracy before socialism is lying to you

i guess it depends on the conditions of the moment. if you're ever in a position where you're using mass action to force congress's hand, i'd think you'd want the shortest ideological distance between your movement/party and its members. if you're not, then it doesn't matter much