I have been considering the batten pockets on my planned sail. For various reasons, (not in the least that they are free and readily-available) I am planning to use bamboo battens myself. Unlike aluminium, they do not come in standard sizes nor are they perfectly straight and they tend to be tapered. That being so, batten pockets would have to be a pretty loose fit, which would mean some would fit better than others.
On Badger, instead of sewing pockets, we used about half a dozen straps, which made it a lot easier to change the batten at sea (you just had to locate each strap, poke the batten through, tie it at one end and then hoist sail up far enough to tie the other end. Much easier than trying to stretch the whole, reefed sail out.) I was wondering whether to extrapolate this concept: make the straps each, say 50mm wide and then line them with Velcro. This way each strap could be held snugly around the varying widths of the bamboos. It is quite difficult to force Velcro apart - it really works by pulling one end and 'ripping' it open; if it did tend to open, a couple of stitches taken on either side would suffice.
I'd be interested in comments. Am I worrying too much about the bamboos being a loose fit in the batten pockets?