Full battens = performance
I recently had the local sailmaker look at our 29.5 main because it nas become increasingly difficult over the last couple of years to flatten the sail when the wind increases. Solid vang, cunningham, main sheet all down hard and the sail still has a huge belly that gets backwinded by the jib and results in a round up.I thought our sail was blown out and needed to be recut or replaced. The sailmaker said the battens have softened and/or were undersized. He took them off and did deflection tests and found that they to be replaced with stiffer ones. He said it would make big, big difference. We can't wait.I just called him after reading your message to check on the status of the battens. I asked him about your batten question. He said that he couldn't imagine partial battens or a mixture on a roach sail that large unless it was a cost versus performance issue. He builds J boat racing sails nationally. Did you check the chanderly on this site for a replacement?Hope this helps,Monty