It's not a surprise to me that there's a manual and that it's even on the device :). But it seems like an iOS design pattern to keep this stuff hidden. I think it's okay for things that rarely happen by accident (multi-finger swipes or so), but touching (swiping?) over screen edges is something I seem to do often, so it becomes a problem. And I'm a geek in my early thirties, so it's not only a problem for the elderly!