pure skill from countless hours of practice. Been there, done that. I used to sail up to the committe boat that a friend of mine was always on. They always had shrimp cocktail and she would hold them out for passing boats. I would keep the boat jusy far enough away so the crew on the rail couldn't reach and then spin the stern up so i could grab it. Drove the crew nuts.
That's a great story. My dad and I would drive right up to docks on Ocean City NJ's bayfront and tack in his Catalina 30. Made people on the dock jump. Pretty fun.