When I were but a lad, and just starting as a sailing instructor, it's what our senior instructor used to say to our novice sailors just to wind them up....it eventually became a bit of a mantra amongst the instructors. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />

Another one was "a sheet is a rope, but a rope is not a sheet" - he was a real PITA!! <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />
of course, it should really have been "a sheet is a line....."