Last night I was waiting in a group to find a healer when some higher levels of our LS agreed to drop by and heal us as we fought. Nice of them :)
Unfortunately, our warrior was terribly inexperienced, but with 4 other melees there (13-15) and two mid 20s healers standing by (RDM and WHM) we did just fine on our first target. But then our warrior (who was NOT the puller) voked a thread leech, and not one but two leeches come bounding our way. Our healers immediately jump on one of them leaving the 5 of us (3 thieves, monk, warrior) to take the other. Only 3 of us barely survived, and one of the deaths was the mid-level WHM who came only to help us out. Truly I had no idea one bad move by a single player could be so destructive.
It got me to thinking.. is there a job where a bad player could hide without ever really being noticed? I suppose anyone who pulls badly can kill everyone, but pulling aside, what's the most benign job a bad player could be?