No - no mechanical advantage from where the line originates. Just more or less loading on the line or boat parts. You can safely eliminate the line from the equation because, in a sense, nothing is moving and the sailor, the righting line, and the boat can be treated as one solid unit. You are simply looking at a balance equation with the mast on one end and the sailors on the other pivoting around the hull in the water. Placing the sailor's body weight further away from the boat and the closer to the water will result in more righting moment.