At to the ultimate "poor man's autopilot" may I refer to the best story of sailing ever written (IMHO), that of Joshua Slocum, who wrote his tale,
Sailing Alone Around The World after his circumnavigation in his sailboat, the
SPRAY begun on APRIL 24, 1895 and finishing JULY 3, 1898. The story is a classic that can be read over and over (for free, with above link...) with pleasure.
As for Slocum's autopilot, listen to this, from CHAPTER XVI, 4th paragraph:
July 17,1897, twenty-three days from Thursday Island. The
distance run was twenty-seven hundred miles as the crow flies. This
would have been a fair Atlantic voyage. It was a delightful sail!
During those twenty-three days I had not spent altogether more than
three hours at the helm, including the time occupied in beating into
Keeling harbor. I just lashed the helm and let her go; whether the
wind was abeam or dead aft, it was all the same: she always sailed on
her course.
As he related in his story, he read many books, caught fish, slept and relaxed the rest of the time.
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