Yes, I just thought there might be more, bearing in mind that Mycroft also (apparently) believes there is a keycode. I have thought for a while that a lot of what Sherlock does on the roof is to lull Moriarty into a false sense of superiority. Look at how Sherlock's expression changes when Moriarty can't see him (but we can, so for our benefit really). Remember also how Moriarty mocks him for believing in the existence of the code, 'Ordinary Sherlock'. I totally agree, I was just looking for a bit more justification and threw an idea out there.
