Dan, the only reason I back the string off is to force the string user to twist the string in such a manner that causes the serving to be tightened. It doesn't really tighten it rather it just keeps tension on the serving. Once I've done a serving you can't tighten the serving by twisting the string between your fingers. If I served the string at 35" and the user untwisted the string by six turns the serving would last as long as a factory serving and we wouldn't want that! If I took the string off my bow and put it on my jig I would still back it off four turns or so.