You must remember that the method explained above is based on absolute data. In other words, it's only as good the the original projections... and as stated... they look well questionable. Also, these are finished cut down and sanded sizes. You'd have to increase them some what to allow for the final shaping and sanding.
The method used in your old picture appears nothing other than an ascending stacked arrangement of progressively smaller ovals (yeap, like that sounds understandable!).
A method for saving wood obviously. No voodoo science geometry.