Wow, that's a cool stave, and a tricky one. It's hard enough for me to tiller those buggers when I have it in my hands but even harder when all I have is some pictures. I use my fingers to make sure there is a consistent taper. I trust them more than I trust my eyes on wiggly staves. I would be paying attention to the bottom mid limb and looking out for a potential hinge forming there. Unless my eyes are tricking me it seems like that area is coming around a lot more than any other area, but it's hard to tell for sure. Keep us updated. Good luck.