The C Scow has a large purchase main sheet. The mainsheet can place a lot of force to the boom.
The C scow mainsheet is rigged either with or without a center traveler.
This sheet controls the C scow main sail. A ratchet block attached to the center of the boat allows good use of the total purchase of the main sail.
When using the mainsheet let it out for increased drive after a tack and when driving through rough water. Pulling the main in hard can be used to increase speed in a puff. Marking your mainsheet in places where you go fast helps you repeat the settings when you need them. Once you become more experience, start to pay attention to the position of the boom and the top batten at different mainsheet positions. Winds of 8-12mph trim the mainsheet so 18 inches of the top batten from the leech in will be parallel to the boom.