Excellent work, Del!
I don't understand why the pieces are glued on at the back and belly? Should they glued on on sideways?
Point me the way ...
They are basically there to just stiffen the centre of the bow where the splice is on the assumption that slight flexing in the grip was what initiated the failure.
Also I think the failure initiated on the back, the sliver of sapwood on the back of the grip is very strong in tension and will help prevent that, further, the glue line on the patches is in tension rather than in shear, so it's giving strength in another dimension.
A bit like how a butt joint has very little strength, but adding a plate either side over the butt join makes it much stronger.
Del