[RichH]

Very good point concerning .... balance points.
Also consider that what balances a boat is not ONLY the *geometric* total of balance points of a sail plan; but rather and additionally, those forces generated by the sails that are *dynamic* (including dynamic efficiencies). If one would simply plot the geometric centers of effort, you could be seriously remiss if you excluded the dynamic effects. Dynamic effects are usually obtained by experience and history ..... and usually are within the realm the knowledge of a good sailmaker or aerodynamic theoritician.