Because singularized thinking on how to play a job is exactly the problem you and Gradd seem to have.

A DRK that only parties with DNC and BRD, only uses Hasso, only uses DD Atma, only deals physical damage... is a crap DRK. They might be doing the most damage possible, but they're useless and generally outclassed even if damage is the only goal.

You don't even stop to consider our thinking, and why we think. You only regurgitate the same schtick that results in turning DRK into some kind of pure DD and ignore any other possibility.