Originally Posted by
ty97
Why AA didn't opt for more of the AAA-BBB-CCC variety rather than doing so much AAA-BBB-AAA I can't say. Doesn't seem to harm anything, though it does drive confusions for fliers every once in a while.
Well, it does harm flyers, because a single flight number for AAA-BBB-CCC gets treated as if it were AAA-CCC for the purpose of computing base miles (and therefore MM and EQM but not RDM any more). The silver lining, such as it is, is that it often means fewer stickers needed for upgrading.