In late September my husband and I did NW TATL MEM-AMS and back, and it was so far from being half empty that you could call it a miserable overcrowded teaming ZOO. If I wasn't gold elite and able to help him skip some of the worse lines, my husband would never cross the pond again. As it is, he was telling people how awful it was. I don't know why DTW-AMS would have more open, empty seats. Maybe your wife just got lucky.