I thought that there was no difference between 9 speed and 10 speed as far as how dished the wheel becomes. Doesn't the cassette take up the same amount of space (rather is the freehub body the same length?) I thought that is why a narrow ten speed chain was required. Please correct me if I am wrong. But if this is the case, the new 10 speed shimano hubs should not need a spacer with 9 speed cassettes and should not be any more dished than the old 9 speed hubs.....? Right?