Curse you and your top-bandedness! I got two band 2 A's and three band 4 A's. And one of the band 4 A's was in maths! That was obviously a mistake. The marker probably hadn't understood the subtleties of my working. Or maybe I lost one of the pages. But yeah, I support the watering down theory. That must be it. Nothing at all to do with the fact that I couldn't be bothered to study for half of them.