On 31 Jan 2012 09:24:57 GMT, Puckdropper
Here's an idea... You lay out the lines on the piece of wood (using a
regular pencil) and the saw detects the lines and cuts the wood. The
wood is enclosed 100% in a sealed environment (add a couple thousand for
HEPA seal) and the user can't get anywhere near the blade when cutting is
in operation.

Sure, but what about the idiot who when walking up to the wood, trips,
falls on his pencil and stabs himself with it? So, you've left out the
step of adding a pencil safestop in your calculations.