I had BA Gold for about 10 years 2004- 2014 while also holding AA EXP, and did a lot of JFK-LAX return during that time. I would credit the flights to AA but use the BA status to get into the FL. The FL attendants in LAX were the worst in connecting the dots, I turned it into a game to see how wound up i could get them. Glad to see not much has changed.