Originally Posted by
40love
How was he able to have a 3 week transit in BKK?
Ummm. He just entered Thailand on the (then) 30 day tourist visa.
From a fare construction point of view the destination was NRT and BKK was a transit in each direction. It was a multi-city journey, but there is still a 'destination'.
From a practical point of view, the routing was built so there was <48 hours in NRT and 3 weeks in BKK. Done this many, many times.