This anti aliasing setting mode is set to enhance application settings. FOR BLADE AND SOUL it doubled fps, stopped the microstutters and all round gave normal, smooth experience.
The hardware is the same; XFX RX 480 8GB GTR BLACK EDITION and a ryzen 5 1600X with 16gb Ram.
My argument for this setting OR the use application settings under anti aliasing mode is that both give a noticeable increase in fps performance on amd graphics hardware/drivers. At least, given hard evidence, it did for me.
TL;DR: REGARDLESS of what your in game setting is, setting anti aliasing mode to ENHANCE APPLICATION SETTINGS OR USE APPLICATION SETTINGS, will give you a better gameplay/smooth experience IN BLADE AND SOUL.
Enjoy the thumbnail ;)