I've discovered the best guyline knot. One that is so tight that no earthly or human or heavenly force can undo it. This knot is the knot that is tied by the wind in your flapping guylines when you are rushing to tear down your campsite and get back to the car fast when a thunder/lightning/hail/tornado storm is bearing down on you. Oh, if only I could tie knots so destined to never come undone.