David, thanks for the explanation of "fun scale." As you say this would virtually elminimate any static score from the judging and simply act as a screening measure for the category "scale." It would just be a contest of "scale flying." To be perfectly honest, though, as someone who enjoys the joys of building scale more than flying, I'd be more likely to enter a "fun scale" competition with a 5 or 0 score on the flying (5 being scale flight, 0 being flying a B-17 inverted) and most of the weight on static judging.

BTW, several researchers in the field of testing have suggested that most people are unable to make useful discriminations on a scale of 10. That is to say the difference between 7 and 8 or 3 and 4 are not statistically significant. People do seem to be able to consistently score on a scale of 5.

I also suspect that any attempt to formally divide participants themselves according to "skill level" (whether that be modeling skill or flying skill) would ultimately be futile. On what basis would contestants establish themselves as "amateur" or "expert"? The only reasonable way to make divisions would be in terms of scoring criteria. For example, "sport scale" could have static scores based only on what could be seen DURING the flight. Expert class (static) scoring could be done from literally inches away. The class you would enter your model in would depend on how you wanted to have it judged.

And just so you'all know, I speak from a position of great ignorance here!