Originally Posted by
Stripe
If AS is in OW what difference would it make even if you're based in an AA hub? You'll earn miles and status when flying AA, get upgrades on AA, etc. To me this would be very similar to the arrangement that NW and CO had prior to 2009. The only issue I see is if you need an agent's help at the airport, it will be a lot easier to find an AA agent in PHX than an AS agent.
OW members don't get upgrades on AA. Unless there's some special AA-AS agreement in place? You also wouldn't get SWUs.
IMO, if you buy J/F or are looking to rack up RDM, then crediting to the best program makes sense; for example if you buy J/F domestically only then crediting to BA makes sense as you get FL access. If you are planning to fly AA primarily and book Y, then crediting to AA makes sense (or AS if primarily flying AS) as you get the benefits of the status you hold.