Where are the knots at in terms of the eventual bow (Mid-limb, fades, outer third, etc.)? You might be able to avoid the knots altogether. You can get away a pretty narrow limb design with yew. I would avoid leaving a cut through knot on the edge of the limb, though yew can typically handle it. Keep the knot encased and leave a swell around it on the limb edge. You can always take more off later.