correct me if i'm wrong, but i think the idea is to use a long string until you get the desired draw weight (eg. 1,000,000#) at brace height (say, 7")...as soon as you can do that, you put on a string which is exactly the length of the bow, nock to nock. This is the string you use until you get the bow to draw length and weight.
I've had the same problem you describe, luke, where you tiller it with a long string, put on a shortie, and one of the limbs shows a wicked hinge or something. It sucks. The preventative is to switch to a short string as soon as possible, as i just described.
radius