Quote Originally Posted by Ashelia_Ferron View Post
Heavy Shot may have a 1.5s cast time but you still impose a 2-2.5s GCD.

Cast time =/= GCD time.

You'll use the same amount of time using just Heavy Shot.
It allows you to use empyreal arrow without having an overlap through the gcd. Hard casting a weapon skill then empyreal arrow is roughly 2.7-3 seconds out of your 2.5 gcd