I would think the Velcro is there to hold the batten in. I assume its on the end of the sleeve where the battens should go in.
yes there is Velcro on the sail where It would hold the battens in on the leach, but the other Velcro part I meant was at the foot of the mainsail, near the mast, on both sides of the sail. Each side has some sort of cell, that inflates with air sometimes, and puffs up, but can be held shut to prevent too much air going in the Velcro. (I guess its part of the doyle design to help put away the sail when its dropped.)
but... should I allow it to inflate?