boarding pass or Amex?
I have the highest level PP thru Plat Amex. I was asked for my boarding pass at one of the lounges at LHR (can't recall which one, T3, upstairs, pretty small, Iberia maybe?) recently and duly handed it over, but I thought afterwards that according to Amex, I needed only show my PP and Plat card. I wasn't asked to show the Amex at all.