Originally Posted by Captain Schmidt

From HK, you have access to CX's network for Taiwan, Thailand and Vietnam which you could use AA miles for at least part of that. If you structured it right, you could do something like HKG-TPE-(HKG)-SGN all on CX and then get a cheap one-way fare to BKK from SGN and fly back to the US ex-BKK (i.e. PHL-LHR-HKG (open-jaw) BKK-LHR-PHL). Air Asia flies SGN-BKK for about USD65 one-way incl taxes if booked far enough in advance.