The original poster was surprised and upset at the rules (he was not aware of ) that AA applies to Admirals Club and Flagship lounge access based on ticket type (not One World status).
Of late we have had an interesting (and informative for me) discussion on One World policies and now also * Alliance.
The original post though was not about One World levels but access with domestic premium cabin ticket.
Readers should know the rules and vote with their Dollars, Pounds or Pesos. I see the role of this forum to help future passengers not to have unpleasant surprises.
As I understand the rules, access to Admirals Club (based on purchased ticket of travel only) is available to passengers flying International Business or International First Class on any One world carrier that day or on a continuous connection the following day (I believe connection max is 4 or 6 hours).
Access to Flagship Lounge is restricted to International First Class Passengers with the same timing restrictions. First or Business Class tickets that are domestic alone do not entitle lounge access. Also remember countries like Canada or Mexico may be regarded as domestic based on itinerary and carrier (American Eagle or code shares may be different to AA.)
So, if you want access to lounges ensure you have a straight through International Connection in premium cabin same day or take your elite One World membership card with a print out of the rules with you.
Alas this will not prevent you from encountering dirty aircraft which are disgusting but my experience is unfortunately this happens on most carriers with ever tighter turn rounds, specificaly including UK carriers. My worst experience was Air Canada SCL-EZE where the previous passenger had removed (presumably) her false eyelashes to sleep on the leg from Canada and they were still sitting on the seat side drinks table, yuk….
Travel is a wonderful way to broaden the mind, I always try to embrace the new and expect different countries to have different preferences and different approaches, that way my disappontments (and I have had many in Europe, Latin America, Asia, Africa etc ) are not unexpected.
I think doing your research is key, which is why these forums and the experience of all the posters are so great.