The filter does keep the lower level folks out and I generally try to set it so that I am playing with masters and pros. Once in a while I will not set it and play with amateurs and give them my tips on the game for whatever that is worth. Most of them seem to appreciate the tips and stay for the whole nine.
When I start a game with lower level players, I always remine them of the green speed. After a round at SA the other day in which one of the pros putted into the burn that fronts the green, I feel badly if they don't know about the green speed.