Blood Weapon / other DRK suggestions:

[Granyala]

...then your points you made actually make NO sense at all.

Actually it makes sense.
While I do love the interplay with Dark Arts, it can be extremely annoying if you factor in all the delays you have in this game.

-UI delay
-Animation delay
- sometimes latency

Making Dark Arts essential in order for a defensive cooldown to be useful severely restricts your ability to react on the fly and use that cooldown.
When you see the boss casting something, it's typically too late to start pressing them 2 buttons, because by the time all of them damn delays in this game are accounted for, the damage will already have landed server side.

If instant spells in this game were actually instant and not some .5+ second delay blah animation must play stuff, Dark Arts would work much better.

I regularly rage about this when using the instant cast thingy on my WHM too.