The term “motor sailing” is used in the cruising community for a variety of different activities. The term is confusing because the root word is sailing which implies that sailing is the primary activity and motoring is the secondary activity.
I propose (only partly tongue in cheek) the following new terminology:
Motor sailing: The primary propulsion of the boat comes from the sails. The motor adds either speed or a better angle to destination. If the motor were turned off the boat would still be sailing.
Sail motoring: The primary propulsion of the boat comes from the motor. The sails add speed. If the sails were dropped the boat would slow down.
Sail stabilized motoring: The primary propulsion of the boat comes from the motor. The sails stabilize the roll of the boat. If the sails were dropped the boat would not slow down substantially.
Motoring: If you are motoring with your main up in no wind and flat water…you are just motoring. You are not motor sailing or sail motoring or sail stabilized motoring. It’s OK. We all do it ;)
Sincerely, People Who Do All of the Above