That's correct as far as oneworld flights go. However you can earn Asiamiles from many other airlines (Dragonair, Vietnam etc) which will NOT earn you MPC miles/points. Also there are times when CX for instance offers bonus miles (they did it for HKG-JNB last winter - 100% bonus). In these instances, you are only credited with the basic club miles, but the bonus is put on Asiamiles. So a HKG-JNB return flight on that deal would earn you 13,260 MPC miles, 2 tier points, and 26,520 Asiamiles (as opposed to the usual 13,260).