I ticketed a reservation yesterday with an excellent agent who knew all of the airlines, booking codes for different classes on carriers.
NB - a portion of the journey is on JAL, the agent was talking aloud as she did the various steps and she stated:
"Always have to remember to open Japan Airlines reservations on a new screen".
It all worked out so that must be a necessary trick.
LHR-HND --- BA (F)
HND-SIN --- JL (J) ----- Destination
SIN-HKG --- CX (J) ---- Stopover
HKG-LHR --- CX (F)
Agent had troubles and referred to Rates and on to a manager in Rates, and it still came back with no YQ (when she told me she had to go up the food chain, I was expecting to get hit and was ready to pay).