Originally Posted by
DMPHL
Added caveat: If you book through BA—even if one of the flights is on AA metal with an AA flight number—you probably won't be able to apply a SWU, because BA controls the ticket, and BA cannot process a SWU.
That's good to know. I am still not sure how one could use BA (who should be able to issue oneworld ticket) to get an AA ticketed for a codeshare flight (LHR - U.S.).