Learn Alliance Flight Path as Horde and vice versa

This trick requires a Priest and another character.
While fooling around yesterday, I found out that if you mind control the Alliance flight master in the Rebel Camp in Stranglethorn Vale, you can right-click him to learn his flight path even if you are horde.
Right-clicking him again presents you with the "You don't know any flight paths connected to this one" error message, so I assume you could use Alliance Flight paths as horde (and vice versa) using this technique.

TL;DR version:

1. Mind control one of the susceptible flight master
2. Right-click him while he is Mind Controlled
3. You will learn the (opposing faction) flight path

List of flight masters that have been found susceptible to this:

1. The Alliance Flight Master in Rebel Camp (Stranglethorn Vale)
2. All Alliance and Horde Northrend Flightmasters

Screenshots:
Learning the Flight path: