Since it's tailored to reach the right people, in this case by looking at
previous participants, it seems reasonable to me to try.
I love the ideas about a QR code and about making it a postcard.
To throw out another idea, have you looked into business card ads? I've
noticed that some bars I dance at will have a table with 2-3 little cards
tossed on there that advertise other dances. I like it, and I think others
do, too. If you like one kind of dance, there's a good chance you'll like
another, so it doesn't feel like litter or like attention grabbing. It
feels like dancers sharing clues with each other. -Lex