Spoken like a true knowledgeable laïque, except for the first sentence, which is spot on.If you are good enough the surface doesn't matter that much.
It's a shot that is used as a 'surprise' shot if you wish. It is not easy. I mean I understand the game but it's a tough one to do. You sort of have to act a bit and confuse your opponent.
When done properly it could be beautiful. You kinda don't know what's coming at you .