BTW -- A friend and I were talking on the phone this morning, and he adds shock cord to his equation as follows:

1) A length of shock cord with a snap hook that goes from the tip of his sprit to the top of the mooring ball, to keep the ball from rubbing on the hull if the current causes the boat to drift over the ball in slack wind, and to keep the boat from over-running the lines and trapping the ball between the hulls. He attaches it from the dinghy when he leaves the boat. Detaches it when he returns. I might try that.

2) A length of shock cord from the tip of one ama to the tip of the other (over the bow). The purpose is to keep the slack bridle lines out of the water and minimize growth (the bridle lines are run above them). I'd do without that extra step - because I think it might interfere with picking up a mooring stick. I use the foam insulation on the bridle so that gets the growth, and I toss that foam at the end of each season followed up by power washing the lines. It's a regular zoo between the insulation jacket and the rope (sand worms, tiny plankton shrimps, etc.).