Looking at a RT SEA-KIX in late June using the "lowest business fare" panel on the far right of the "economy" screen. So picked an outbound SEA-SFO-KIX on UA at approx $3700, then go to return fares. Most of them are similar amounts, but part-way down the page, for flights involving a leg on Asiana, e.g. KIX-ICN-SFO-SEA, the fare is shown as $0. OK, just for fun, select that & get an all-in fare somewhere in the $4000 range. BTW, an all-UA RT prices to approx $7k. Can someone explain this ... does it get an all-inclusive RT fare or a magic glitch in the software. If so, maybe I should buy a Lotto ticket.