As far as I know, what I have seen from personal experience, is that this only affects the visibility of games in Gamespy. You can still join a game, even a Gamespy game, by connecting directly to your host's IP. The order you patch in has no actual affect on gameplay itself. Its just for whatever reason, when Gamespy looks for games that match your version, it is distinguishing between "patch a to patch b" vs. "just patch b."