" Nock travel or paradox" ? Well, when you have perfectly straight and level nock travel, overall paradox is reduced significantly, and thus makes for much easier tuning and also allowing a wider range of spine, even when shooting fixed blade heads.Early conventional Solos prompted the deluge of mechanical heads into the market, simply because of their horrible nock travel. Couldn' t tune a fixed blade to save your skin on the earlier ones. Eventually the solos evolved to a point where you could realistically shoot a fixed blade out of ' em without pulling your hair out, and the reason behind this is due to better nock travel and little else. Guys couldn' t figure out why they had to " bounce up a couple of boxes" on the charts with early solos, and there are two reasons for this---one, the manufacturers had to increase the draw force curve in an attempt to bring the solos into competitive speed with the twins, and two, because of their horrible nock travel. As stated, they' ve come a long ways, but with the hybrids there is now simply something much better within the industry that offers unmatched nock travel and easy tuning for all. JMHO. Pinwheel 12