Hey Murph,

If you need more flattening in the top of the sail, I suggest you try adding some mast rotation. The unstayed portion of the mast, above the hounds, bends sideways on its minor axis. The more the mast is sideways to the leech, the more the leech tension (ie: sheet tension) will bend the top of the mast. More bend will give more flattness.

GARY