Thank you all for your explanations.
BD's second mission was to sail in shallow waters. If I understand correctly there are a number of proposals: 1. a schooner rig without need for rudders 2. partially pulled up rudders and play with the balance of surface jib vs mainsail and sheeting on the balestron 3. Frisian style sideboards
Lowering or raising one of the sails on the balestron at each "tack" seems more crude than continuous differential sheeting on the schooner. Of course, replacing the balestron with a schooner rig is not a trivial refurbishing.
Luc
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