Leash line on a windsurfing board? That's something that's usually frowned upon because there's a lot it can tangle on (like getting wrapped around the rig or your legs when waterstarting) and a windsurfing kit typically won't drift quickly if it gets away from you because when the rig drops into the water, it acts like a sea anchor. The most important thing is to make sure your u-joint is in good shape because if the u-joint fails and the board and rig separate, then the board will definitely take off downwind faster than you can swim. Personally, I would ditch the leash. If your swimming skills are weak or marginal, wear a float vest. They're a lot less bulky than a full on life jacket, but they provide adequate flotation, added impact protection, and they won't interfere with your harness hook.

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