mad max,
You are correct. Depending on course layout and length, our "teams" would consist of two, and on very long races 3 riders. Each rider would be slated to ride a section usually dividing the mileage up as evenly possible.
On the longer races that ran through the night,(Baja 1000, Vegas to Reno) I would normally ride those sections as I was very comfortable riding at hi speed during night conditions.
Most of the off-road events were two rider affairs. There was at the time only one rider of record, so only one rider would end up as a "points" earner toward the championship.
Mike