I participated in one as a student.
Not only was it an intro for my husband into "my world", but it was a good intro for me into con-Ed workshops.
It was a voluntary extra taught by our instructor, but we did it at a local yoga center instead of the clinic/classroom. We had to bring our tables, sheets, etc.
Yes, it was the basics: intent, draping, body mechanics, effleurage, petrissage and tapotement. After a short introductory talk, the student therpists gave their partners a basic Swedish as the instructor described what we were doing (if necessary).
After a break, discussing how it felt, etc, the students became the clients. The instructor talked the husbands and friends through their basic Swedish, and the class was small enough that each pair received good individual attention.
She taught couples massage as a nurturing touch we might not be accustomed to by itself. It is important when working with a spouse or s/o that both stay grounded in massage and keep the right intent.
Hope this helps?