Farm dungeon mounts without getting locked out!

The maximum dungeons you can clear each hour is 10. However due to a recent post by Gihelle (Minor: more than 10 Instances per hour) we can see that the restriction applies to realm location (US, Oceanic, Brazil, etc..)
After some tests, I can confirm that this restriction actually applies to individual realms rather than realm tabs as mentioned in the original post.

That means you can farm the following mounts 10 times on realm A then switch to a character on realm B and farm them again:

http://www.wowhead.com/item=13335/deathchargers-reins - Deathcharger's Reins - Stratholme
http://www.wowhead.com/item=63043/re...us-stone-drake - Reins of the Vitreous Stone Drake - The Stonecore
http://www.wowhead.com/item=63040/re...the-north-wind - Reins of the Drake of the North Wind - The Vortex Pinnacle

For maximum efficiency you might want to do this with a rogue with Nightstalker and Burst of Speed talents for 205% constant movement speed!
Monks and druids are also good, but not as fast as a rogue.

Good luck farming the mounts!