I wonder how often the itinerary called for Flam rather than Eidfjord. That's where the "one-off" description might fit. Our Flam RR excursion called for a stop at Voss on the way back with a meal at it's "famous hotel." In reality we stopped at the Stalheim on the way to Flam. Maybe it's a matter of when Viking can get a bloc of tickets on the RR?