"European side-wheelers, such as
PS Waverley, connect the wheels with solid drive shafts that limit maneuverability and give the craft a wide turning radius. Some were built with paddle clutches that disengage one or both paddles so they can turn independently. However, wisdom gained from early experience with side-wheelers deemed that they be operated with clutches out, or as solid-shaft vessels. Crews noticed that as ships approached the dock, passengers moved to the side of the ship ready to disembark. The shift in weight, added to independent movements of the paddles, could lead to imbalance and potential
capsizing. Paddle tugs were frequently operated with clutches in, as the lack of passengers aboard meant that independent paddle movement could be used safely and the added maneuverability exploited to the full."