Thanks for the responses, guys!
Half eye, there's no whoop te doo in that spot, that sliver is just one of the several separated laminations that ended up outside after the calamity befell it. Did I jus say calamity?
Thanks, Mox, I thought it was looking good too. I had a little evening-up to do on the opposite limb, but this one was impressing me (up until the bang) with its nice circular tiller.
Badger, I was at about 50# and 28". There wasn't much set up until that point, I'd lost maybe an inch off my reflex near the tips.
Leroy, I think I'll be throwing every precaution I've ever heard of into the next one. I'd thought of backing this one, but I like the natural knotty look. There weren't any nicks, either, maybe a few dents from clamping not very carefully, but there's no evidence of a dent where she blew.
I just got back from my buddy's place. We set his moisture reader at .78 (since that's what I got by dunking the wood earlier). 0.0 it said. We thought it was just not reading the wood, like maybe we weren't finding a flat enough spot for it to register. Finally I set the SG down a bit, to .72, and it read something like 2% moisture content. I thought "this can't be right, ok what if I erred in my measurement, AND the wood I tested had some moisture in it when I tested it. I set it down to .65, then .60. The highest moisture content reading I got was about 5%. And there's no way the specific gravity of the wood is that low. So obviously, the wood was too dry.
Maybe it would have failed anyways, maybe not. But I weighed the stave immediately after heat treating so I could monitor the re-hydration process, and 3 days later it had LOST moisture if anything. Obviously this dry prairie winter air prevented rehydration.
Once again I asked Santa for a bow, and once again I got socks.
Oh well, this setback coincides with another trip home to the farm, there are many potential bows still standing! Maybe I'll be optimistic and cut some arrows too...