Huh...I am doing the same thing tonight. I have a .5" board I am trying to taper with my toothing plane. Doubles as aerobic exercise. I was just gettin online to see if I could find some recommendations for how much the tips should taper to for a Bamboo backed bow and found this... Tapering from 5/8 at the handle to 1/4" at the tip seems like a lot of taper, (particularly since it would take about a week with the toothing plane). Did I understand you correctly? I was looking to remove about 1/8" of belly wood from fade to tip, taking it from 4/8 to 3/8. Is that enough to get an even reflex/deflex bend in the form?