A common mistake in my experience is to try to point too high in light wind. Crack the sails off a little and sail a couple of degrees lower. Make sure you have some twist in the sails too. In light wind the difference in wind velocity is greater from sea level to mast height. The higher velocity at the top will look like a lift up there. Hence the twist in the sails.
Your sails should have the basic telltale setup. On the main, you should have telltales on the leach at each batten pocket. On the jib/genoa, three sets are needed about 12-18 inches aft of the luff and spaced evenly. Place the telltales at the points where you would fold the sail if you were to fold it in quarters from the head to the tack. Sailmakers typically put three on each side at the lower location for the helmsman to steer to. Set the fairlead so that the jib telltales all break at the same time. Other than that, in light air just try to keep the telltales all flying.
Somehow, J30s got the reputation of being weak in light air. I don't know where this comes from since we usually kick butt in light air. It is hard to get weather helm at times. Load the crew to leeward and forward to heel the boat and induced some weather helm. Loosen the rig some (before the race) if you know its going to be light. No backstay on at all. Get a solid vang to hold the boom up in light air so the main can take its designed shape.
I've never read or heard of any techniques for dealing with heavy swells in light air. Anybody else got experience in this area?
