regarding booking ahead. I have a solution to booking ahead. It's
called "booking behind". Instead of looking at people's heads when
looking for a partner, you look only at their behinds. Normally, you
can tell a person's gender from the shape of this part of the body, so
you can locate a suitable opposite gender partner. However most
people don't remember an individual's behind, so this guarantees a
certain degree of randomness in partner selection.