Yew Stick Bow Explosion

I've been working on a Yew stick bow (from a 2" diameter pole) I was doing it pretty much free hand just trying to use it as it came. I was aiming for 70# at 28" which was maybe a tad optimistic.
It was moving nicely, beginning to get the tiller looking nice at about 24" draw, low brace and 70#.
I'd just done some tidying up and was giving it plenty of exercise on the tiller when it went bang.
There was a big knot going right through the back at the arrow pass. I'd been hoping the bow was stiff enough there, but obviously no! The back parted, if I'd rasped out a scoop and patched over with clean sapwood it would have been fine.
Anyhow, I'm not too worried as it was just a quick experiment, and fortunately I hadn't wasted the time or effort of putting horn nocks on it.
I did a couple of vids, one during tillering and an autopsy!
https://www.youtube.com/watch?v=ynQa9JxAmJo
https://www.youtube.com/watch?v=HaxxoqOy9jU

Meanwhile on the Primitive Archer forum, one of the guys in Wales was having trouble making a wooden crossbow prod, only a light weight 40# one, but they are tricky due to the short length and can easily end up too thin or too heavy and chrysalling on the belly. I said I'd see if I had any suitable off cuts, and found a nice slat of the Walnut that I cut with my brother back in January. I cleaned it up, sawed it to a thickness taper of about 1.6mm for each 6" of length and posted it off to him, there's a bit of deflex in it, but than can be a good thing IMO with a crossbow prod.
It'll be interesting to see how it performs, as it felt quite lively when I tested a small off-cut.