The problem with "Instant OFF GCD" abilities makes combat feel less rewarding.

[Rin_Kuroi]

Anyways, just my own input. Not entirely certain where people are coming from with complaining about this because I honestly don't see what is wrong in the first place.

Animations block the use of certain skills. If I want to use Atherflow + Lustrate (two instant cast abilities) to heal the tank I have to wait for the animation of Atherflow to finish before I can use Lustrate. Since just about everything has an animation this is effectively a GCD for all abilities even for non-GCD ones.