I've been denied access to the BA F lounge despite being QF Platinum (which has special access rights at LHR on BA, in theory same as BA Gold, and not the same as AA EXP) when not flying BA and having BAA terminal access rights. BA is doing a hard sell to force people to fly BA these days, and out of LHR BA thinks they have every route covered (so in their view the pax has no good reason not to be flying BA). The OW alliance is a bit shaky these days. BA was much easier about lounge access in past years, so just because it used to work doesn't mean you will get in this year (2006).