I can`t believe I`m reading this - sailors in the first world still use string to hold battens in, with those plastic batten-ends that have a V-cleat in them ?
This can only be due to those one-design purists who won`t let you change anything about a 1960`s design, so you end up living in the past. Long live Hobie.
In the third world, at the southern tip of Africa, we use an allen key to adjust our batten tension. Of course, we sail a development class, so we`re allowed to use nifty gadgets that were invented AFTER the first moon landing.
The Hobie sailors here still use string. There`s nothing quite like being class-legal. The fact that anyone still uses dacron sails also amazes me - why not canvas ?

Just kidding !
Steve