I can confirm that this works for horde, but it's really tricky to find a good spot. I am a druid and I stood in bearform casting Faeri Fire (Feral) to damage the mobs after 1 hit (rougly 1k-2k hp lost).
The irritating part of this is that you aggro the guards, but they hit for only like 90 dmg/shot with their bow so aslong as they are in range you can heal or whatever, but remember that if you do FF on a mob and have hots up, you aggro them.
Guards hit 2-3k dmg on me with melee, so stay in range!