I'm with Bill. As with most measurement systems involving math and increments on a fixed scale, it's prone to mistakes. Parallax errors, inaccurate calculations, conversion errors, inaccurate instruments and poor eyesight.
A direct, unchanging system or device is always superior. i.e. story sticks, 123 blocks, key way stock and SET UP BLOCKS.
'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton
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