Now, mileage monkey says following routing is valid... but you never know what the agents might say...
Please comment away following routing.
ICN-HKG-YVR-MEX-YVR-MEX-YVR-MEX-LHR-MCT-LHR-IST-LHR-NRT-CGK-NRT-ICN
Whopping 49,869 miles.

Note all the YVR-MEX flights.
Now, not as exciting as my current DONE4 (taking me to places like SCL, SYD, IPC, DEL)... but almost same amount of mileage for about 1,000,000 KRW less!
About 10 cents per mile... inclusive of estimated taxes when booked with AA, which I think is a pretty good deal in premium cabin.