With my more limited experience with yew, I'd have to agree. I've only made a half dozen yew bows, because I live in an area that has no yew trees, and it's very expensive for me to obtain. I've made several higher poundage longbows tillered full compass with high density yew (40+ rpi) which seem to be holding up just fine after many shots. I've also made some shorter length bendy handle low density yew bows, some backed with rawhide, and these all took on about twice as much set.
I respect Mr. Bickerstaffe. I spent a few hours in his shop, and was able to learn a vast amount in that short time. He was a very gracious host. However, I do disagree with him on a few points. The one about a yew bow being "shot out" in only a few months doesn't hold any water for me. As I said, I have several high poundage yew selfbows, and after several hundreds of shots, they all seem just fine. Also, yew will make a bow out of very marginal material, as opposed to other woods which would be junk. Yew is tough stuff. It just seems to enjoy bending. It's also very easy to work, as it's a softer wood. I believe much controversy exists with yew.