For further guide, I look at the spin luff looking for, lets say a knuckle or bend in the luff not due to wind. When my halyard is all the way up the luff is tight, you can grab the luff and try to turn it and get nothing. I usually have my spin haylard eased 4"-6" in light to moderate conditions. Moderate and above tight. I would prefer to be able to ease the tack line, but I have an end pole snuffer. I had a sailmaker out with me one time who was trying to figure out the 6.0 since he was making us new sails. at ont point we had the old Worrell style spin up and needed to get above an obstacle. He eased the tack line off so the tack was near the leeward bow and I could drive much higher. Not sure about going faster as Dave points out...