I have a masthead rig. The luff on my 100% jib will only allow the sail to go to about 4' from the top of the mast if I secure the tack to the deck. i can easily add an extension to raise it 2 or 3' thereby increasing visualization under the jib for cruising. I think it will line up better with the foot of the main so that air will flow from jib past main instead of having the bulk of the air flow under the main. Would this cause excessive heal? Would it be faster or slower? How should I determine how high I should place it?