My experience in getting NW intra-Asia awards has also been very bad. If you can originate from NRT and have date flexibility (i.e. can book inside the 3-week window), your odds might be OK, but just try getting from BKK to anywhere through NRT.

They did slip up in 2003 at the height of the SARS thing and, with great difficulty, I was able to book BKK-NRT-GUM-CNS and vice versa as a CO elite. They were apparenly so mad that someone actually did that that 3 months later CO created a special award category and doubled the miles required.

As for CO, luck has been better there, but generally only on CO-only itineraries unless it's to/from NRT (in which case you might get a single NW segment thrown in). But if you're in NW-only markets like BKK, you're hard pressed to get much at all. And with DL weak in Asia and adding its own people wanting flights, the situation for U.S.-Asia trips just gets worse.