So Cathay will be quite relaxed about having SQ fly A380s on SIN-HKG-SFO, and if SQ gets the rights to operate SIN-HKG-NYC what will they use on that? A380s will be operating SIN-LHR, DXB-SYD, MEL/SYD-LAX, all similar length routes to Cathay routes. MEL-LAX was one of the deciding routes for Qantas to choose the A380.
The original 777-200 non ER as chosen by Cathay is the aircraft that struggles to carry meaningful payloads over longer routes. Over shorter routes it carries a lot of extra weight compared with an A330-300 to carry only a few extra passengers.