I had no problems with "supervision", although I assume my room was searched daily and monitored. We were on a group visa with a bunch of other military members and the tour guide was trained/licensed by the Chinese govt, so again I assume we were monitored. The thing is, even though both as a group and as individuals we were potentially interesting from a surveilance point of view, China has opened up so much that there are probably far too many interesting visitors to really spend as much time on each one as they used to.
That said, our photographer insisted on not being able to speak much english and he somehow managed to find a seat on the bus near 2 majors, and he "slept" most of the time, but in general we hate talking shop during our free time even when in the states so it certainly wasn't too hard avoiding sensitive topics. If he was taking notes, the most he got was some griping about how we hate the fact that they're firing all the finance officers so now I have to be an expert on thousands of rules regarding finance even though throughout history, military finance in every single armed force the world has ever seen has required carefully trained administrative staffs to keep the average military member from screwing it up. If they're interested in that sort of crap, all they need to do to satisfy their curiosity is visit the air force personnel center website and take a peek at the force shaping news, and request a copy of the budget from the US govt publishing office. Or subscribe to the AF times and aviation week...
Anyhow, once you get over the fact that you're going to be monitored potentially 24/7 and the only way to avoid it is to simply not go on the trip, it's easy to just accept it and enjoy the vacation. The only concession I made the entire trip was I took zero electronic devices with me on the trip except for my cameras, and both my cameras and all recordable media were in my posession for the entire trip without exception. I even carried my camera battery charger with me. Saved me a trip to the cop shop to get my stuff x-rayed for bugs after returning home.
