I expect MC to fall in the first week by hardcore players. Most guilds and early pugs will also steamroll it into the ground when they get there. 3-5 weeks in, as the masses hit 60, then we may start to see fail pugs. There's still plenty of brain dead people out there who will just stand in fire and ignore all mechanics, but MC can be 15-20 manned and those players may struggle to get into the raid in the first place. I don't expect players who refuse to learn to ever make it past MC.