The only way to increase boat speed for given sail drive is to reduce total drag, which can only be achieved by reduced wetted surface of the hull (friction drag) and effective displacement.
(friction; drag; ) (The only way to increase boat speed for given sail drive; is; to reduce total drag) (total drag; can only be achieved; by reduced wetted surface of the hull (friction drag) and effective displacement)
friction The only way to increase boat speed for given sail drive total drag
drag is can only be achieved
to reduce total drag
by reduced wetted surface of the hull (friction drag) and effective displacement