Soul Calibur V - Quick Neck Buster (a:g:A)

Well, everything is crucial in this move. There are some moves that have a "main secret" (ewgf of DJ on T6 and Asura Dance Just of Kilik of SC4 are examples). But aa has no main secret. Every "letter" is a fast slide, but you are using a "help button" with the second "A" (propably that is the reason you heard that). So, input a fast slide a:g, then press "A" right after that ("near together", I mean).

Ok another thing. Where exactly is the fastest input crucial? I've heard that the important part is between g and the second A, does that mean the speed of the first a to g doesn't really matter as long as the a gets canceled?

I think it´s easier this way because you already use the right hand to do the fisrt slide. I think is harder (the position) to input everything using one hand. But if you can do using this way, no problem, the slide is the same.

Any reason you put it specifically on a left trigger?
Because i am using the right trigger. Just curious.