Knots or not, I keep the belly flat if I can. If it is a run of the mill pin knot on the belly, I just ignore it. Not disagreeing with Hamish as I believe he is right in that length, width, weight and draw length are all part of the equation. I simply don't leave the belly built up around a knot like those. Osage can handle it as a rule. The bigger it gets, or if it is hollow or punky, I may leave the tiller a little flat but that's about it, but that is just a matter looking at the knot and making a judgment call really. Knotty staves I will go longer as a rule so that the stress is less on any one area. This bow had knots galore. First pic is during tiller and second is a recent pic. Most were a non factor. Some were voids along the belly edge that I filled with super glue. I'm not sure that most other woods would have held up, but this one is fine. Flat belly worked as normal, left just a little flat on the bad ones along the edge.