Most FF plans combine mileage earning and status. On CX those are 2 separate plans. MPC is strictly status (no award redemption) and Asiamiles is strictly awards (no status). I suppose it is this way for commercial reasons (Asiamiles is a separate company and used to be used by several arilines -- something like the old SR Qualiflyer plan). This happens to also be the reason that Asiamiles can be used on more airlines than just CX (upgrades on BA for example), making it unique within Oneworld.