I suspect he may have meant what Bmorv mentioned. Usually when folks say, "You don't have to chase a growth ring on whitewood staves", they don't mean that they violate/cut through numerous rings with abandon, but rather, that you don't have to chase a ring because when cut during the growing season, the bark will pop off with ease, revealing a pristine, unviolated single growth ring that is then used for the bow's back.