Yeah, It has been hard to explain this well in that short text in ways that anyone could understand. 

Outbox does receive your posts. But that's irrelevant. The reason that list exists is to let your followers know where to get it. The app will send to other relays as well, but your followers should use the Outbox list to get your posts. 

And yes, the General relays only exist because of the old model. My current thinking is to add Tor so that the app can connect to random relays out there to download posts via Tor (so they don't track you). Meanwhile, the app uses the General List as the "authorized relays" to connect to and download posts.