I think what everyone is missing is that currently everyone is running these instances with CLASSES and not JOBS.

You are making due with CLASSES that were not intended to party based play, so of course party make up is going to end up on the extremes. (Extreme tank + Extreme Un-tank+ Nothing in the middle)

As JOBS are supposed to equip CLASSES with more party oriented abilities, I am sure that once JOBS are issued this will be somewhat of a dead discussion.