The pattern that everyone hopes to get when setting up a set of gears is usually not possible. When you have set up a lot of gears you come to realize that fact. It has been my experience that for one getting a good read on the pattern is hard to obtain because it is hard to get enough resistance on the ring gear as you twist the pinion into it to get a good reading. And just as it states in the Yukon guide, you should "look only at the pattern position from face to flank"
