You can get around this achievement in pretty much the same way that you could boost ranked battles in MVC3.
You and your boosting partner go into your Xbox's settings, you both change your location to some oddball country or location (make sure it is the same one on each console). Restart your Xbox. Now when you search ranked, only search for your region. Sometimes it still takes a bit to find each other, but at least this way, you should only find one another.
This same setup can be combined with many of the other ranked achievements.