Shoopman

While looking around at various combo threads, I have come across the notation AC (whiff) in all of them. I'm assuming that it means what it says, activating your AC at a time when it will not connect with your opponent. Can someone explain the functionality of whiffing your AC mid-combo? Is it acting as somewhat of a poor man's RC to extend your combo with moves that do not cancel into each other naturally? It seems that the opponent would be able to block again after you whiff your AC, so I am a bit confused as to why you would want to do that.

As someone just starting out, which skills should I focus on to get up and running ASAP? I'm rolling with Arakune for now, but that is subject to change once I actually know what I'm doing. As it is now, my play is basically organized button mashing. I can pull off one of his ground combos, but hit confirming into it is another story. I want to get to a state where every input is intentional, but I feel like if I focus too heavily on one thing, than all the other areas of my gameplay will suffer. Any advice?

Brand new to this game and BB in general, and I'm thinking about choosing Arakune as my main. I have a very basic question: What can cause your 6d bug (the one that looks like Weepinbel) to miss after a combo? Is it strictly a timing thing?