Many Blizzard games allow to cancel animations, so units can move farther while shooting. Warcraft (DOTA) and Starcraft are good examples where you can invest APM to make your units more effective.
I found this video where some guy demonstrates this for the Demon Hunter. It seems very effective and you can move farther than "normal" kiting where you wait for the animation to finish.
Is this also considered a bug, like the higher DPS with clicking? Should I bother to learn how to do this or will they fix it? I mean it is a bit unfair as melee characters do not have this option.