Exploit #1 - Leaving so soon?
Mind Controlling an enemy out of an instance portal in Warsong Glutch removes them from the instance. This is fairly simple, and extremely annoying, it is easy to avoid however, unless the opponent has the flag and are waiting by an exit portal.

Exploit #2 - Hide and seek
Can't find the flag in Warsong? Lucky you, just stand near the middle of the instance, load up the score sheet, and manually /target *enemy* and Mind Vision, the only people you cannot find like this are Rogues while stealthed, however, stealthing removes the flag from you, so nothing is lost.