He does some wonderful night photography and he also does workshops and tours around the West.
Regarding your original post, I tried ISO 6400 on quite a few shots and tend to try to stay at ISO 5000 or lower if possible. And, even though you originally found it frustrating to have to wait for the in-camera High ISO Noise Reduction, I think you will find it is better to wait the 30 seconds or so and not have as much work to do in post production. Royce talks about it on his site, but there is a formula for the maximum exposure time based on the focal length. Some use 500 divided by the focal length and other use 450. Roughly 10 seconds on a 50mm lens or 20 seconds on a 24mm lens, for example. Anything longer and you will likely see longer star trails than you might want.