all you have to do for more accuracy is make your final tablesaw cut right next to the centreline instead of through it...to state the obvious:) nice tool, I'll go make one for myself now...
Slight modification to make it more accurate - drill the center large hole, then get a board with a dowel attached to it, the same size as that hole. Mount the board to the drill press, with the dowel offset from the drilling axis the distance you want the smaller holes to be away from the larger hole, then drill one hole, spin 180, and drill the second hole - and both holes will be exactly the same distance from the edge you are using to locate the center of the circle...
Perhaps you could have used the compass to determine the position of the 2 dowel holes referencing off the center-line in 2 positions, then you wouldn't be depending on the accuracy of your 90*
your silent video says a lot... makes one think... this tool is similar to a Center Stanley Square tool 46-101 which there is no you tube information on, thanks for sharing...
This is a rather elegant solution. If you really designed this, you should patent it and get it produced in a machine shop. Incra? Someone would snatch up the rights to this for sure.
All the work and the tool is not accurate. Also not really good idea to touch the forstner bit with your hand while the drill press is turned on. Wait until some home owner/amateur who wears gloves while they work decides to clean out the bit and the glove tangles up in the bit. That bit is small yes, but imagine on a larger bit?. GOOD ON YOU!. Lets think before we create videos that are not safe.