IMO, the "no ring violation" thing is mainly applicable to Osage as it's early/late growth is like alternate cast iron and chalk.
Yew is vastly more tollerant. Here's a pic of the first ever Yew ELB I made, it's still going strong some 40 years later and shows where I had to reduce the sapwood at one point and step down through about 8 rings!
where it became V thick and there was a big dip in the heart wood. It's still a fast bow at about 70# @28".
BTW. That's an old pic. That bow has been pulled to 31.5" abused and refurbished with the belly heat treated, and 40 years of experience put into re-tillering and adding horn nocks. It shoots faster than when I first made it and is fine.
http://bowyersdiary.blogspot.co.uk/2014/04/refurb-progress.htmlAt about 1:20 on that video I linked to you can see where I've had to drop down a few rings near the tip, again it's to avoid running out of heartwood. In the commentary I mention the difference between Osage and Yew.
Del