I did Zerg it in 10man, with 1 pallytank, 1 holypriest, 1 hunter, 1 warlock, 6 random melees.
My paladin's armory :
http://eu.wowarmory.com/character-ac...anz&gn=Eutopia
As you can see, 1st Yogg kill on that char = Yogg 0 less than 7 minutes. Really THAT easy in 10man (Tank and healer died around 2-5% of yogg's health).
We then tried it in 25man, well with the same strat (tank piles up adds and dps go all out on the boss), It just didn't work, worked well until 1st beacon, then boom no more tank.