Ah, Herbert!
You are referring to my favorite telescope! It's a pleasure to hear such accolades for it's legendary optics coming from you!
Alas, I don't have the answers you seek. However, there is a history of the company that one of the Dynascope Yahoo group members put together (was it Rik Hill??) It might be on that web site.
Also there are some astute members of that group who may shed more light

on the subject!
Ah here is the article--don't think it fully answers your questions though.
http://www.lpl.arizona.edu/~rhill/DYNASCOPE/criterion.html
Hmm, this may remain a mystery perhaps. I'm grateful to those unnamed folks who figured that glass so well. Try polling the yahoo group.
Regards,
Gerald