Yeah, I like to take matters into my hands, a bit too much, too.

There have been several instances where I'll run a High or Expert, see no new player bonus, and a DPS will do mechanics wrong, or die to needlessly easy mechanics. At first I try to be the good person and ask them if they understand the mechanic, or flat out tell them.

However, if they choose to ignore me, and I have to keep wasting my mana to cleanse, heal and rez them... I will start taking matters into my own hands. Letting them suffer, or flat out die in hopes that'll teach them the lesson. But.. there have been times that has backfired because either mechanics that don't necessarily happen to the healer start happening to me, or it causes the mob or boss to take longer and everyone starts running out of resources, etc. And once or twice I've caused flat out wipes because of it. >.o

I like to think I don't do that anymore, except for an all friends group where it's common place to joke around. But a player who is ignoring everyone's advice, and catches me in a bad mood...