This is not a mystery.What's all this talk about the Enigma being undecipherable? It was little more than a character scrambling electric typewriter. Why are we mucking about with Quantum Cryptography if the Nazis already invented an unbreakable code generating machine? Undecipherable? Hogwash! Maybe back in those days. How often did they change the 'key'? Could it even be changed or was it hardwired (geared?) into the device?
Extensive writing on this subject.
Poland role impressive