Originally Posted by Columbia9_6
Instead of shot gunning the problem, I'd suggest starting at the beginning. Someone said earlier fair the bottom. I assume they are referring to a new bottom paint to reduce unwanted drag. Next, loosen all your standing rigging and tune the rig properly. contrary to an earlier post, two year old dacron sails are new... two year old laminates are not. Properly cared for dacron sails will last 10, 12 years. Balance the boat when sailing. If it's not balanced, nothing else can be repeated on a consistent basis. Then you can send picture, gps tracks, apparent wind readings, etc. we can provide a lot of help with just a little more data as long as the conditions are repeatable...eg a balanced boat.
I didn't say two year old sails went any good, I said they would start to effect performance. If you look at any racing class that uses Dacron sails (the J-22 comes to mind) there is a definite replacement cycle for sails. When I was racing the 22's we replaced the sails before every big regatta. So a new set for midwinters, new set for nationals, new set for North Americans, ect... A jib with 10 races on it is a noticeably worse pointer than a new one.
Note that this would be stupid for cruising/day sailing, even performance sailing unless you are sailing at the top of the fleet.