AremRed wroteThree man should be learned in 1) camps, or 2) low level games like Middle School. You should never have a guys first three man game be a Varsity game. I should know, my first three man game was a Varsity game. It did not go well.
I'm going to guess that less than two, or three, percent of the varsity games in my little corner of Connecticut, are three person games. I would bet my house that zero percent of subvarsity games are three person games. In fact, I would go as far as saying that there are more one person subvarsity games than there are three person subvarsity games.
My first, and only, experience with a three person game was a boys varsity game in a holiday tournament. It could be described as a "big game", which is why three officials were assigned to that game. Previous to that, I had only studied three person mechanics in the manual, never on the floor.
One year, we had a voluntary, preseason, one hour, "on the floor", three person demonstration by our interpreter. Only a couple of dozen officials showed up. This demonstration hasn't been offered since.
For some officials on my local board, their first three person game is a state tournament quarterfinal game. The only exception would be those officials that also work college games, and there aren't too many of those.