I used to do something similar to this, but my way is less efficient.
>Be Horde
>Borean Tundra, on 310% speed flying mount waiting for ship from Stormwind to Valiance Keep to appear (usually near the iceberg in the ocean, a litle way away from the harbour - they'll usually be unmounted/or on non-flying mounts and can't get away)
>Gank those on the boat, mount up, fly to the respawn point at the farm where they auto-respawn, and kill them again
>Being a Death Knight helps, because when they respawn usually they'll be throwing some buffs up/eating abit before flying off, you'll reach just in time to chains->grip->kill.
While waiting for the boat to appear again, you can check out the profession trainers' corner, Inn mailbox, or flightmaster for lv72-80s. You can even see them flying in and get ready for them.
Alright that's all. *Hides*

