True, but friends also don't waste the time of their friends by standing in the defile or chaining frost tombs in the raid.
If you have agreed as a guild to raid, you also need to agree to perform at a particular level.

Otherwise it's simply an expensive lesson in repair costs and guild resentment.

wow partners are not friends, unless you know them irl from before

To the downrated poster above me, You are wrong. You can be friends with people without ever being near them. Yes the friendship will become stronger once you get to be with them personally but that doesnt mean that they will not be your friends before.

As for the topic, I've done lich king + 11/12 heroic kills on 10man with hardcore players and it felt good. After that I've strugled with my guild to get the lich king down also on 10man and it felt a lot better.
One of the best feelings in the game is being in a group of friends, and finally defeat a boss that's been killing us for ages. It happened back in kara and again on icc

Blowing and insulting everyone and pointing out flaws in a rude manner will never help and people will not want to play with you again.

@SamLowrey: that is an awesome idea! Such a dungeon, even if relatively simple in its implementation, could really help role balancing in the game (particularly the shortage of tanks) for a long time to come. Don't award any xp, loot, emblems or gold, but just allow a player to run it as many times as they want to get comfortable with a role. Throw in some of the less complex mechanics (rage timers, imobilizing factors like bone spikes, etc.), and that's a great foundation for dungeons and raids. Additionally, if they could allow you to go in with partial or full groups (and just fill in any empty slots with AIs/NPCs) then you can have friends/guildies provide you with helpful tips. Shame this will probably never come to pass. :-(

Bah! Wrong comment thread! My bad.