So, if these results are correct (and if we also ignore what people are talking about the ProController having less input lag than the GC Controller for some reason, and using this result as totally true), the difference between the Pro Controller and the GC Controller is, visually, something around half of a frame, and maybe you will lose one frame sometimes. This maybe can impactate a person playing in a tournament, but for anyone else playing in their houses with their friends or over the intenet... I don't see any advantage in change a wireless controller with a lot more features for a wired gamecube controller. For me is more a cost-benefit function, and lose 1 frame to have better confort while playing is fine for me.
I understand that, but the A button being already my default position where I rest my finger anyway, it doesnt change anything if it's bigger.