There's currently a bug affecting the guards on Tol Barad Pennsula.
as an alliance player (i'll use a druid as an example) if you tag a player with moonfire and Insect Swarm (you can run out to about halfway across the bridge) run back to your base and stand by the guard, the next tick of Moonfire/sunfire/IS/etc will tag the guard onto the horde player.
i play a horde player, and trust me its retardedly annoying.
i'll try to get some fraps going tonight, or some screenshots.
To condence it down: Alliance players can Tag there Base guards onto horde players with Dots, at an incredible range.
gonna have to find someone to help me get a couple of good screenies (or a video) up. O__O