Yet another update, and perhaps the last one as this thread goes (thanks a ton for all of the feedback, btw).
The group of us decided to form our own guild, starting with a focus on Heroics with an eye towards Karazhan when the time is right. Included in this guild was the mage.
We decided to try a run at Heroic Ramparts last night (first time in for me and our regular War (now specced dps)). Party setup was Prot Warrior, Arms/Fury Warrior, Frost Mage (ya, he specced back), Survival Hunter, and Holy Priest. First pull went down no problem (2 mobs). Mage got aggro from the solo patrol at the entrance and he and our tank died. I gave a mild rebuke over Vent for a near-wipe on a solo mob out of carelessness, and we moved on.
A few more pulls and we get to the Orc fellow who summons the Hounds (Beastmaster?). We wiped because we didn't realize you can't CC the Beastmaster and despite being non-elite, the Hounds hit awfully damn hard. Mage announces over Vent, "We can't do this...I'm out." DPS Warrior talked him into staying. He had already broken two of my traps up to this point and I made the comment in Vent (with careful attention to making it sound lighthearted) that if he kept breaking my traps, I was going to start shooting his sheep.
Yet another few pulls and the mage's sheep breaks, his mob runs over and 2-shots him, and he "disconnects"...not to return for the rest of the evening. We found a replacement and cleared the instance.
I logged in today after work to find he had left the guild. I talked to the dps Warrior and we both agreed that he would not be welcome back any time soon. It's not that he's a terrible person, he just doesn't take feedback very well at all. He either ignores it and/or takes it personally, and he's so focused on cranking out the dps that his own CC mobs kill him and then he blames the tank for not picking up the mob in time to save him. Turns out the dps Warrior had put together a Botanica run this morning from which the mage bailed on them as well. It's one thing to be a little thick and defensive, it's another thing to bail on your guildies twice in < 16 hours.
Regardless, thanks again to all of you who offered feedback. ^^
