There are Tanks that pull when both healers and DPS have no mana...
There are DPS that pull when tank and healer are not ready...
There are all kind of bad people, welcome to internet.
If u are a Tank/Healer u are not a special snowflake. U need 5 people for a group, and each one of them is an equaly important member of it.
Ive entered so many RDF Groups where Tank didnt have a single chance on holding aggro on 3+ targets over my Best in Slot Retri paladin (cos he was slow, bad, not geared as much as i am).
Instead of trying to Taunt and Tank the mob that deals a lot of DMG (preventing it from oneshoting me), while i burst everything in my way, he complained constantly.
I even let him Tank mobs for 5sec before DPSing, did 1 Divine Storm, instant 2/3 targets on me...
After that i got some defencive items and rushed my way trough the instance (healing myself aswell, helping out the healer).
Wana know what he did? Voted to kick me arround 10 times, and didnt DPS/Tank at all...
Did i make a forum post about it? How tanks think they are special and that we should have a 10 hour 5m instance cos they are slow? Even tho i could tank it and carry him trough the instance? No...
Its a game, all kind of stuff happens in it...
If the tank is bad, if he takes 10 hour breaks before the pull, ofcourse im going to try and speed up the run a bit. Like u wouldnt.
If its a overgeared DPS taking aggro, killing everything in his way, try to tank the BIG npc that can one shot him, and let him tank the rest of the small ones...
If its a dickhead, beeing a smartass, pulling everything and killing people, vote kick, or just let him die and go without him.
If its something else, find ur way out of it, u wont become a better player by QQing on forums.
Again, if u are a Tank or a Healer, it doesnt mean u are Special (nor u are special as a DPS player)...
Play the role u are playing the best u can. If u dont like the group, leave, make a little break, go back in RDF que, repeat.
Or simply join a guild, do RDF with friends only, so on...