G'day, Mast position is critical to the "centre of effort"... The mast position is adversely independant, and must complement sail configuration ( as I'm still experimenting with this concept) which can be affected by weather the condition... in addition keel position and length,(ie light to moderate and fresh to strong, long keel, or short keel, thin or robust). One must experiment with this conjectural option. I wish you every success... M Easton