Marc, I had the same exact thing happen to me a while back. I had spent many hours hollowing out a highly-crowned character stave, from an Osage sapling pole I felled, and when I started bending it, I kept hearing little ticking sounds. Sure enough, that thing split right down the center of the limbs. I just sat there looking at it completely deflated. But I will say that I had wondered prior to that build, what would keep a wooden bow limb from suffering the same radial grain line checking, that occurs when felled logs are left full-round and unsealed. When you cause the crown of the limb to flatten, every one of those radial grain lines are trying to pull apart along the belly.
-That said, I have made a couple of slightly HLD (shallower in the belly) bows - one Osage and one CrepeMyrtle shorty - that did just fine. I like the idea and the science behind it, not to mention they look sexy, but once you see one split itself in two, it kind of makes you take a step back.
-John
