So had an idea today was browsing Wowhead.com bored and came across Global Thermal Sapper Charge - Item - World of Warcraft
Supposedly this item does 1500 damage to walls, towers, ect in WG. So my idea is this, get a bunch of engineer friends and guildies into a group and wait behind the keep up in icecrown for WG to start.
After WG starts, fly around the invisble walls and have everyone bomb the gate to the WG relic.
WG Relic wall gets destroyed, friends run in cap, game over?
I havnt been able to test this but for anyone who knows a bunch of engineers or even wants to get a group together spamming in trade "LF Engineers for 30 sec WG" or w/e it should work.