From a die creation standpoint, I've often wondered how on some dies: 1. Only the Central Device is Doubled. (Above Coin - Some 1966 Kennedy's) 2. Only the Lettering is Doubled. (Typical Eisenhower Doubled Die's - Some 1966 Kennedy's) 3. The entire die face is doubled. (1955/55 Lincoln - Some 1966 Kennedy's) It "almost" makes me want to believe that multiple steps occur in the die creation process of perhaps master hub with only the central devices and a master hub with only the lettering? But I know better since the blank dies are conical in shape and therefore the first contact with the hub is generally in the central area of the die.
Nice find. I found two out of dealer stock years ago. Sent them both into the old ANACS where they forwarded back to you the picture certificate. I only got verified. Years later I sent into PCGS with request to grade and verifiy DDR. They graded one MS64 and the other MS65 in 2nd generation green slab, but did not at that time verifiy the DDR. They said AT THIS TIME it was not one they did. So I sold the MS64 with ANACS certificate and still have the PCGS MS65 green label and ANACS Certificate.