I have used the anchor knot. Easy to tie, easy to undo, but won't come undone. It is also compact, you can easily make the tail almost zero, & it yields almost full line strength.
http://www.apparent-wind.com/knots/anchor-hitch/
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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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