I think Macca has already done this on his super Taipan. I agree with you Dermot - those windsurf batten tension adjusters give a really clean finish to the back of a sail. Given that on sails with low strech material (vs. Dacron) you do not need much batten tension (other than the top couple of battens) then I would think that velcro pockets would work on OK. That string is a pain in the butt when you have cold hands.

Chris.