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.
Once again, this analysis is correct.
The position of the line has no bearing on the amount of righting moment applied to the system. Another way of looking at it- if you were able to make your body completely rigid and affix your feet to the bottom hull, there would be no need for the righting line (essentially make yourself a cantilever beam). You would have exactly the same amount of righting moment without the line.
And how would standing on the tip of the lower daggarboard change the force/torque diagram?
With or without (like I was just standing on the board) the righting line being applied?
Standing on the tip of the daggerboard makes the sailor taller, i.e., it move's your CG farther away from the bottom hull (the fulcrum) so it increases the righting moment of the system.
For example, if you're 6 feet tall & 200LBS, with your CG 4feet up from your feet, then leaning horizontally, you can produce a righting moment of 800 FT-LB. If you stand 2 feet out on the daggerboard, you can now produce 1200 FT-LB, so you increase righting moment by 50%.
sm
