I know this is an old thread, but I checked it out before a recent flight and I am sure others still do as well.
I tried using the card in 2 airports, CDG and DUB. In CDG, they still have the old swiper where they get an imprint of the card, of course, it worked.
In Dublin, they have a really new facility and swiped the card into their database and of course, I was asked to leave.
I got the card when I signed up for Amesx Plat. I cancelled Amex and got the letter stating that the card was cancelled.