Well, apparently they were being strict this week on our return flight from SFO. Two bags, each at about 26 kg. Wife left her carry-on bag at home. And so we were stuck with one overweight bag (after transferring 3 kg from one bag to the other).
Seems somewhat unfair to me. We had two checked bags, each at about 26 kg. Additionally, I had one carry-on bag, weight unknown, but would guess about 5-6 kg. Wife did not have any carry-on beside her purse. We got charged for one overweight bag. If we had had something to put the extra kg into to carry onto the plane, we would not have been charged overweight. And so the charge was not really for the total weight, but just how it was distributed.
Worth writing to KLM about?