This is an old thread but it can still be useful to someone. The Cal
Boats of the 1960s were flush decked and the sides were almost vertical. This includes the Cal
20,25, and 28. Because of their relative high freeboard the sides would act like a vertical wing. If anchored bow forward you would sail back and forth. This was caused by the wind
blowing across the sides of the boat. One side would "lift" and start "flying" sidewise. Eventually the vertical wing would stall or quit flying and the boat would start back the other way. Then the process would start again and keep repeating back and forth. In a tight anchorage we would solve this problem by running the anchor line off of either corner of the stern. The boat would settle down and not sail or swing back and forth. This was in the sheltered waters coves off California
so we never had high water
over the transom. It worked for us!