Another option is "all of the above." http://forums.ddo.com/showthread.php?t=294454Umm this is more from ignorance (only have one fighter to higher levels) but it may help to better define what qualifies as a tank....
I have an understanding (correct it at will) that there are three tank modes
AC tank - you don't get hit and (with U9) can do just enough damage to maintain aggro to keep the Boss of the moment on you so other mobs or bosses/mini-bosses can be covered by the others. A better AC tank also dishes out enough damage and hate gen to keep aggro if others also start beating on the boss. This is harder vs. pure DPS characters - and thus sometimes the DPS's just need to slow down a little to help maintain SP outflow and keep the boss under control.
HP tank - two forms of this really first is the healing amp tank (ie. full heals from cure lights) to minimize SP required OR just massive HP tank that can actually take a full, maxed out heal maxed 10% and still need more. These guys are easy to keep alive while others take care of trash/minibosses and/or other bosses. Again as a team you need to mitigate your damage output so the aggro stays on the boss in order to help keep SP use efficient.
Hate Tank - hits hard and often, keeps the bosses attention through pain and suffering. May need more frequent healing than the other two but rarely loses control of the boss due to being out-DPS'd.
Each of these tanks is viable in degrees and depending upon the group makeup one may be a better choice than the other. Knowing which of these you are and which you aren't is important. Knowing that you are none of these is important. Thinking you are one of these and being proven wrong in the quest means you should step aside. Thinking the star chose the wrong style and messing up the quest because you didn't want to stick to the stated plan should get you booted.