Frederik, I bet that should be doable. However, even with my unbalanced sail on Ingeborg, I can carry at least as much sail downwind as upwind (or rather a bit more) before thinking of reefing, so there is not much to win, speed-wise.
Only if I were to race for silverware, would I bother with installing the at least three more control lines needed to let me wring out those extra 3-5% speed downwind. For my cruising, I prefer the half-short batten parrels, which make reefing easier.
Arne
PS; I must add that Ingeborg has a good rudder, so is not the first to need a sail with adjustable balance...