I'm trying to optimize my HF setup, but I'm not really sure what it does. From wiki:
Delay is not reduced to zero, or any other set amount. Attack rate is still based on the delay of your weapon. Higher delay weapons will still attack slower than lower delay weapons will.
I've heard theories that it actually caps magical haste, so keeping haste gear on would actually be beneficial, however if its a set rate that is not affected by haste gear, it'd better to go full ACC/ATTK. Has anyone ever tested this? Looking for testing methods and ideas here if not.