You said flat-out it did NOT work. I'm saying that it's not determinable, and so far, no published security holes in Skype exist. In fact, no real good details exist, despite plenty of people trying. Skype's probably the most popular IM/Voice/Video protocol in the world.

I agree that Skype's protocol may be terrible. But you cannot state that obscurity didn't help. "No one" is even able to connect to Skype, let alone break it, at this point.