Kudos for the Naval History series. I felt the need to comment on this one. In sailing, a sheet is not a sail, it is the line (rope) that controls the sail. In a heavy storm, sailing ships would often "hove to" and lash the wheel windward and sheet jibs windward as well. Allowing the forward most sails to backfill would help to keep the ship on course and try to maintain some stability. A ship with three jibs sheeted was in the worst possible conditions and would appear to be rocking back and forth, while slowly making way forward, much like a drunken sailor.
Again, your explanation is in the right ballpark, just wanted to add a little to it.