While sailing on Saturday; 15-20 knots, mild chop; I still couldn't point well and maintain speed. I was sailing in the groove of the jib telltales. The mast was really misbehaving and flipping all over the place, and the windward/aft diamond wire was very loose.

My theory is that the diamond tension was too soft which leads to the mast bending significantly which leads to reduced rig tension. The bendy mast flipping all over the place will also affect the shape of the main adversely.

Any mozzie sailors with experience in improving pointing ability? Am I on the right track to improved upwind performance?