I recall exactly the same thing happening. A domestic hop, then change to the long haul and cross the Atlantic. Due to the connection being late in, I doubted that my bag had made it. Once I saw how many folks were still waiting at the carosul, I knew the answer before the poor admin person arrived to give everyone the surprising news! My how they screamed. My silent scream was exactly the same, 'They knew this 7+ hours ago' because the airline would have known before the 7.5hr flight was even off the ground. If they had made a cabin PA when the doors were opened, they could have saved some
PR. My bag arrived the next day (just one rotation on that route) and I was perfectly happy.
That was (just looked up my diary) 1999 and the airline was LH. The connection was from MUC to FRA and on to DTW. So I think I can say that your KLM/AMS experience is par for the course.
It's the lack of antcipation and lack of use of data they already have but, as with many other factors - that takes a little money and a lot of good mgmt.
