yes Celestar340, I believe Hong Kong Flyer and I know.

But it is still a bizarre fact that (at least for my comparison above) for flights bought at the same day, flying the same dates and hours, with the same carrier, with the same flight numbers, with the same restrictions(Saturday/Sunday night, 21-days in advance), the Zurich-Frankfurt return tickets are much costlier than the total for the same flights adding the transatlantic return segments.