you know, paul comstock says that a bit of natural twist in a stave is not a problem, however if it was due to the tillering, i would fix it, just check either side on the offending limb for thickness, if one is a tad thicker , sneak it down with a scraper, you will be surprised how little you have to take off, make sure you exercise it well after each tiny bit, wood "training" becomes very apparent with an exercise like this- its easy to land up with twist in the other direction if you take too much off, and will only notice it after the wood settles in during the exercising.
wayne