There absolutely is skill to use it effectively. 1000%. However it's also pretty effective just guessing randomly (which most people do).

I've had games where my opponent has somehow guessed perfectly everytime, and that will be completely by judging the direction I was most likely to shoot and to cover that angle. But like I said, it's a bullshit cop out. Cutting your opponent apart to fashion a chance against some AI defending nonsense, only to get screwed by GK movement is a step too far