i agree with jetaisnoobie, it really is an easy to master class. you just need to always be open minded and take those "you suck cause you didnt do it this way" remarks as a chance to grow. never hurts to try something new out. im still getting people that have never seen a tank do the best tanking method in copperbell mines HM and they applaud me for telling them and teaching them how to do it. now i have had a few that say "omg, why did you do that its so much easier in the middle" lots will belittle you, lots will hate you, but when that duty completed comes up you will bask in the glories of gold and women! it takes a calm headed person to be a great tank. thinking clearly in those stressful situations is the best thing you can do.

Speaking from a healer standpoint it really is an almost easier job than tanking on MOST fights. From a dps standpoint, i mean come on, dps is so incredibly easy in MOST fights as well. Every class has their job to to do. Bards/monks need to silence, tanks need to rotate CDs correctly, healers need to preheal massive damage spikes and remove debuffs. the list goes on and on for stressful situations.

tl;dr- all classes have their stressful situations. IMHO: tanking is no more stressful than dpsing or healing. certain bosses have different party checks, its up to those who are checked to figure out what to do in those situations and for the party members to help them succeed.