Quote Originally Posted by Giantbane View Post
With normal skills, you can press the button when there's only about 20% of the GCD left, it will queue up the action send it to the server, and then as soon as the GCD is up on the server it will immediately execute the action.

However, macros do not let you do this. So what happens with your macros is you need to wait until the GCD is completely up. Then you press the button, and then when the server gets the message it will actually execute the ability. This slows how fast you execute skills in unison.
I will test this when I get in game. But in all honesty, I do not think that Reprisal falls into this category because it is not on the GCD so the macro forcing the action to wait for the GCD to completely end is wrong, and I have seen it work in my favor every time because I can literally mash the ability (or just simply press the button again during the GCD) and Reprisal is cast immediately, no delay at all.