Re: Overlapping versus Blade headsails which is quicker ?
bill, I'd suggest you have to experiment because among other things it wil depend on the specific boat and rig. For instance, on a J/24 the spreaders may ship from the factory two inches longer than the class association requires. If you're on a stock boat, your 150 will hit the spreaders two inches before it needs to.
But if you cut the spreaders down to the minimum length (yes, take a hacksaw to your rigging!) the genoa now comes in two inches closer and you can point higher without tearing the sail.
Polars? Theories? A good set of polars should in theory tell you what has been found fastest on your boat. All well and good, but sometimes you need to check everything and then experiment. I'd bet the condition of your sails (main and fore) and the shape they take is going to affect that as well, so what works best on one boat, just may not be the fastest on the other.