We appreciate your contribution, no really we do. Pew spewing really speeds up those dungeons for the Healer and I, and we like that. However, there are a few things you could do to make our lives a bit less frustrating.
By all means use all those abilities to Max out your numbers and I appreciate that you may be learning what they all do, but please please please, don't press that knockback button. Seriously, I realize it comes in handy while you're leveling your squishy moonkin or shaman, but when I've just used all my cooldowns to get those casters all standing in range of my cleaves, your knockback just screws everything up. You see if a caster isn't silenced he'll just stand where he is and fire off armour ignoring spells at will at the person on top of his threat table. And if he's out of range of my melee AoE, then that top threat person will quickly cease to be me, the high stamina, damage reducing tank, and rather be the significantly more vulnerable healer. And that's not even mentioning the knockback into the next group.
In a similar vein, if you see a caster or a hunter standing off to one side shooting at the tank, it's probably not wise to attack it. As instead of the usual competing with the tank's 500% threat generation, you will competing with a bit of residual threat. Much better to attack one of those enemies your tank is pounding on - preferably the one with the skull above it.
I won't harp on about pulling for the tank, you should know better. Or about those 3 repetitions of g and o that you love so much. Trust me, it really makes me want to slow down - and possibly - take a smoke break (I don't even smoke). But just generally, if you make my game feel like work, and not the good challenge type of work, but the annoying disciplining preschoolers kind of work, then I'm not going to go out of my way to keep you alive. And I may just throw it in for now, after all my next queue will very likely be as quick as my last one.
And a very special mention goes to the moron retribution paladin who thought it was a good idea to cast Hand of Protection on the tank on every cooldown, completely cancelling his threat and sending mobs everywhere. You are a schmuck.