on my tiller tree, my marks come from the belly, because i'm always using staves of different thicknesses. So I just do the math every time. Easy peasy. If the stave is 1" thick, like the white oak holmegaards i'm building now, then when i pull it to 23" i know it's 24". If the stave is 1.5, and i draw it to 22.5", then i know it's 24". No problem. Seemed to make more sense while i was making it to measure off the belly.