I made this list from recent comments made in a forum thread by Ghostcrawler WoW lead systems designer. Bold and italics are mine.
1) Do not run with bad players
2) [...] if they stand in the fire, overall you have to understand that when you are signing to up to be a healer you are signing up for the primary responsibility of keeping the raid alive.
3) [...] if the idiots stand in the fire, guild kick them. If you don’t have that power, then find a better guild. “Blaming the healer” is to some extent a social problem.
5) [...]if you don’t enjoy healing [...] I’m kind of at a loss for why you raid.
6) I was saying stand up for yourself a little bit. If you are wiping on challenging content, then you need to step it up a notch. If you feel abused by your raiding group, and can’t get that behavior turned around, then by all means, find some better friends.
7) [...] the responsibility of healing the raid is yours. The responsibility of doing things that let you do your job is that of the dps and the tanks. If the tank doesn’t blow her cooldowns and then blames her death on you, she is a bad tank.
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