It's so nice to run a raid when everyone is up to snuff on their characters and can focus entirely on what their doing. Unfortunately there seems to be at least one person who is not at the top of their game. Either the healer that's standing in fires or the DPS that can't fight their way out of a paper bag. They're not bad people and they mean well, but they are better cheerleaders than raiders. What's a raid leader to do?
I like to help people out and give people a shot, but there's only so much that I can do. At some point I have to consider the needs of the other nine or people in the raid over the needs of the single player. I was leading ToC 10 with a Hunter pulling 1800 DPS and the entire raid averaging about 2700. We had a number of wipes, but low DPS was a contributing factor. I called out the DPS saying, "Guys, I really need to be seeing 3K DPS." The 1800 Hunter said, "I don't think Hunters can pull 3K DPS." I nearly fell out of my chair.
My first response is to try to offer quick suggestions for how to resolve an issue (this is considerably easier when it's a raid awareness problem rather than a role problem). I feel genuinely awful when I have to remove someone from a raid, but the raid environment is not where one should learn his or her class.