After reading a recent article by Erwin Putts about Cosina's own glass making factory I now know what Mr. Koboyashi was up to.
"Recently a claim was made that Cosina owned a proprietary glass melting factory where glass is being made for use in the Voigtlander line of lenses. The corollary of this claim was the inference that because of this fact (creating and melting their own glass) the Voigtlander lenses were better than others who had to use glass form the main manufacturers. The basis argument is the one I have sketched above in the paragraph about the Leitz glass lab.
It is indeed true that Cosina makes their own glass. They do this in small amounts, just for their own demand. It would be not possible to create the same range of glass as is available on the world market, so the glass that Cosina melts is of a limited range."
The link can be found here...
http://www.imx.nl/photo/optics/page146/page146.html
Cosina must have been doing a great deal of private experimenting for the new Nokton.
Best Wishes.