The lower the line, the harder it is to hold on to - but it doesn't change the static equation. If the sailor, the line, and and the boat are not moving in relationship to each other, no change in the position angle, length of the line will affect the amount of righting force being applied. The line weight is negligible and the center of the weight doesn't change either. Only the sailors weight and position is important - not how he's braced there.