RE: bow string question
Just depending on what all has crept and how much twisting the cable will increase the draw weight. However it also makes the draw length longer. How many twist you need will depend on how much creep has occurred and how how many twists are already in the cable to start with. You just have to experiment. What you may end up doing is twisting the cable and the string to put more prestress on the limbs while maintaining proper cam orientation.
If you want to put nocksets on the string then have at it. Nobody makes strings with them already on the string. And I never found them necessary in the first place. You'll be quite pleased with Gibblet's strings. Much better than anything you're likely to see from the factory. And way better than Zebra strings.