The Framer says it doesn't matter where QF international flights actually go as long as they go and are fullish. If EK end up running into LHR and QF pick up secondary ports with 787's that EK don't operate to or are skinny on, then that's fine. EK pick up the feed of Australian domestic frequent Flyers and a couple of LHR slots (win). QF pick up EK frequent flyers when they arrive in Ausralia and when they want to go east out of Australia and NZ (win). As long as the two airlines choose ports that they don't compete heavily on then it will be win/win.
They will have to design their joint network carefully to achieve that but hopefully that is what they are doing right now.