Depending on which toon I run a random heroic on, I react differently to many different situations and my personality changes completely.
When I'm on my warrior tank, I'm having a blast charging around and rounding up mobs and since I do over 3k single target dps and over 5k multi target dps, I really don't care what anyone else is doing as long as I'm getting heals. I never complain about my group members, for the most part, and people thank me for tanking in my fashion.
When I'm on my mage, I do over 7k single target dps and a crapton of AOE so I can carry dps through most heroics. As long as the tank is decently fast, I'm happy and I very, very rarely leave groups.
However, when I'm on my druid healer then I get cranky and mean. I joined a Heroic Gundrak group in progress and when the feral druid was pushing about 500 dps, and I was outdpsing him WHILE HEALING, I stopped healing him. After he died and said "my bad", my response was "yeah, your bad." Then "i don't heal people i outdps," followed by "back to dalaran with you scrub." He left the group in shame.
Or I just yelled at a tank for a minute or so and left group last night in Heroic Nexus when the tank stopped between pulls and was doing about 800 single target dps.
This isn't some rare occurence, I'm generally much more mean and much less willing to put up with shenanigans on my healer.
The only time I will get nasty on my tank is if the healer asks me to slow down for mana in an easy heroic like DTK. I just respond "I don't need your heals" and keep pulling. But even then, I'm nowhere near as mean as I am on my druid.
Anyone else this way?