Unlike sailing to windward, on a run, the angle you sail to maximize your VMG to leeward depends a lot on wind velocity. In heavy air, it’s fast to sail almost dead down wind, while in light air you must sail a lot higher. This relationship is not linear. In lighter winds, under 7 knots, & heaver winds, over 13 knots, changes in wind speed have only a modest impact on your ideal sailing angle. In the middle range, a small increase or decrease in wind speed can change your optimum sailing angle significantly. In this “transition” zone, you must be very sensitive to changes in wind speed.