Mike,
In general, I know a reasonable amount of top player perspective (if not ability) is required.
As an example, many engineer or LA trained gca's tend to drain fw to the nearest spot, even if that creates reverse slope or blind fw. I recall some firms tended to create crowned fw to get them to drain, which worked, but created rejector fw in both directions! Somehow it never occurred to them that it drained and made the course virtually unplayable for everyone.
At the same time, many of the tour pros who get involved with gca tend to misuse their knowledge. I see a lot of "what if I miss it here?" type questions affecting the gca, and of course, the real answer is, if there is no penalty for missing anywhere, where is the nuance and strategy?
That said, given you are designing for the 99% of non-top players, I sort of question whether any expensive nuance aimed at just 1% of players really, really makes the difference in design. Even many top players prefer the "what you see is what you get" design, and a "receptive to a good shot" design, which doesn't really require any special high level playing knowledge to pull off.
We just need to know how far a typical carry is and some other basic criteria to create holes good players like. Now, creating all the quirk, nuance, and whatever the typical gca.com participant likes......well now THAT takes a lot of knowledge!