I tried to run Heroic Grim Batol with guildies last night. We got to the second boss the Forgemaster. We could not get past him because of the stacking DOT on me (the tank) when he swings 2 swords. Looking things up on the internets and they just casually say to dispel it. Problem was no one in the group could dispel magic.

Eventually we will be able to just outgear, dps, and heal it. But it was quite frustrating to be held back by a single mechanic such as dispel magic in a 5 man.

My point is, you may need to think about all the buffs, debuffs, and other minor things that you never needed to use before when picking your team.