I haven't tried this myself, but someone posted this on FT a little while ago, what you need to do is when you book the award with AA don't select your passenger profile, but select new passenger and enter a name and DOB that happen to match yours. Then, once ticketed, you can add your AS MP number to the booking. Then you should be able to get your MVP benefits like free MCE and preferred boarding. I think that's the only time this would make sense, if you're AS elite but not AA elite. Also I don't believe you will earn AS EQMs in that case.