Really, they should be kept as short as possible. Otherwise you're changing your draw length. You buy a bow to fit as far as draw length, poundage and all that to get the most you can out of the machine efficienc wise. If you end up shortening the true draw length to accomodate som long string loop you loose power and efficiency. All you want is enough room to quickly and efficiently hook on you release and not be bumping the nock with the jaws. I even changed releases when I went to the loop.