Originally Posted by anabolism

Thanks for clarifying. One option would be signing up for a new AAdvantage account, as there's a good chance AA won't catch it. However, you'll have to manually change the frequent flyer number of each trip, and my recollection is that when you remove your AAdvantage number from a trip, it drops off the list of trips that show up when you log in. The iPhone app, at least, lets you add trips back in, and they tend to stick since they're cached locally, but I don't know if the website allows this.