I dont want to turn this thread into "Medical care for Medicare recipients living overseas".

To summarize and conclude: I've been exchanging detailed PMs with rbAA and have spoken with a Kaiser NorCal Medicare plans broker, who has conceded that rbAA has found a way to viably make the system work for him, as well as being legal assuming rbAA returns to the US for at least 24 hours once every 4 months of being outside US. The broker admitted (threatened?) that Kaiser's system is not "yet" set up to "catch" people who move out of the service area but keep an "active" mailing address in area. Broker added that emergency service is supposed to be allowed only within the first 60 days of a out-of-area trip. I countered that Kaiser receives a capitation fee per month from Medicare and anyone who is actually living outside the area is not using Kaiser services and thus saving Kaiser money, and that emergency services in Thailand are much less expensive than cost of similar procedures in US; so, its a win-win for Kaiser and for the expat (but a lose-lose for Medicare and taxpayers). But then I realized I was veering into old-man-political-ranting territory and the call was being recorded so I shut up and thanked the broker.

rbAA and other expats are fortunate that this is working out for them.