A side thought on cost and logistics:
Would guys expect to pay less for a 'timesharing' scenario than a one-on-one session? Or same? Or more?
If an SP could book multiple guys as a shared session, would they expect to charge each guy more, same, or less than the one-on one rate? Would they prefer group encounters (less hours of work per day, tougher work), or individual sessions (more hours, easier work).