Linking discounts (genius and getaways) with multi-day stays.

Hi

The only limit I know of is for promotions.

I get what you mean i.e. don't allow discounts for single one night bookings, which makes perfect sense.

The workaround would be to restrict rates to a minimum of 2 nights.

I think a min. of 2 nights is  best solution. Too much work for only one night.