I think one can have to much twist in a string. I used to build all my strings with as little twist as possible so as to allow for future twisting as the string(dacron) stretched with usage. I also pre-stretched them with a 2 ton jack arrangement I fabricated, and let them sit on it for 24hrs before sending it out with a bow. All my strings were 3 braid twist so I didn't have the out of round problem. Once in a while I would have a customer state that the arrows he had been shooting well for quite some time, all of a sudden were not flying good for him. Upon sending the bow back for me to find what the problem was I notice the strings were EXTREMLEY twisted. Upon further discussion, I found these were original strings sent with the bow generally 2-3 years old built from dacron B-50. A new string solved the problem in at least half a dozen cases. I can't explain why, I just know a lesser twisted string solved the probem. just my .02 cents