On a personnal experience, as a WAR, you're expecting far too much of the dungeons. Story dungeons are just here to show beautiful graphics, really. And for the myth farm dungeons, be happy, whatever people can try to each you, you'll probably fail 2-3 times before mastering the mechanics. One more time if effectively everyone is new and thus noone can teach anything.

Even knowing perfectly how to do the coil 2 weeks in avance, I still wiped like 10 times for T1&T2, and T4 is still as hellish as it was the first time I tried. Knowing isn't what determines how you succeed. Practising is