Bruce,
As stated previously, when the aircraft RVSM certification requires operation in RVSM with the autopilot engaged, then it's got to be engaged. Further, when the operational authority documents of the company flying in RVSM stipulate that the autopilot will be engaged, then it will be engaged.
Each aircraft I have flown in RVSM required that the autopilot not only be functional while in RVSM, but be engaged, and when level required that the altitude hold feature be used, as well as the altitude capture be utilized when climbing or descending in RVSM. This was also a company requirement at each operation where I've worked, per the approved company manuals and guidance, and this left us no options but to comply.
Hand flying up to FL290 and once again below was often practiced and encouraged, but not while in RVSM.