I called the NW Elite line today on this subject: She Who Must Be Obeyed is meeting me in Germany for the last leg of my trip next month and has a 3 1/2 hour layover in AMS. I asked about a day pass and was told they are only good in in US but was told the 30 and 60 (or was it 90?) day passes are just like the "real thing" and would be valid at the KLM lounges in AMS.
I will of course double check this before I spring -- I might be willing to attempt battle with the KLM lounge dragons but She would probably walk away (thereby wasting my $90
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