With the A340-300 carrying so few pax, they can load up more on cargo, something the A340-300 has an advantage over the B747-400 (if I'm not mistaken - if I am, I retract that statement). If you've noticed, the configuration of the 193 is as follows: 8F, 60J, 125Y. They've increased the J load over the standard 343 by 50% and the Y has been taken down by 35%. They basically have got the premium load of a B747-400 without the excess weight that a B747-400 would be if it flew empty.
CO has a EWR hub, CX has a HKG hub, UA had neither, especially from the originating end. It had the worst inflight service of the 3 to boot.
If it so desired, CX wouldn't have to reduce the capacity of the HKG-YVR-JFK route by putting a 343. They could just reduce the 2nd daily flight HKG-YVR to a 343 (for all 7 days) and leave the 744 on the HKG-YVR-JFK run. That way, premium pax who would fly on the 744 (one) to YVR will be forced onto the HKG-YVR-JFK 744 (two).
I agree that when the A340-600's come, the one-stop can be canned though the YVR-JFK link is the only direct link between the two cities. I don't know how much traffic there is between the two, though cargo has been ignored in your post.
Cargo is profitable for airlines. Don't just talk about pax, there's cargo as well.
I wouldn't bet against CX on this one, their service has a big reputation. And they may even get feed from SYD. I have relatives in HKG and NY State, my mum has friends in YVR...I could do a SYD-HKG-JFK-YVR-HKG-SYD trip and earn a heck of a lot of points.
M88, 722, 732, 733, 734, 73G, 73H, 742, 743, 744, 752, 762, 763, 772, 773, 77W, 320, 332, 333, 345, 388, DH8, SF3 - want