Jeremy Zawodny wrote:
FWIW, I'm not trying to dispute the validity of that coverage or
discourage anyone from documenting contests, I'm simply trying to find
the reality behind it.

Udo already provided half of the answer (592 pilots/teams have
participated in at least one SSA sanctioned contest in the past 3
years). Now all you need to do is figure out how many active glider
pilots there are in the US...

Marc