The problem with not documenting things is that developers like me are turned off before we start. I don't want to bend the platform so far that it breaks. I want the limits. I'm tired of reading stories about apps being pulled for using private APIs, or breaking in future versions because they're removed. I want to do things in a supported way so I can make everyone happy.
Right now, I can't even see the boundaries of what's possible, because nothing is documented. I don't even want to try to write for Apple platforms, because it's entirely inscrutable and unpredictable.