It is believed that the Combined Cipher Machine was never broken by the Axis , although a British test cryptanalytic attack made considerable progress , the results were far worse than against the Enigma , due to the increased complexity of the system and the low levels of traffic .
It is believed that the Combined Cipher Machine was never broken by the Axis . 
 Although a British test cryptanalytic attack made considerable progress , the results were far worse than against the Enigma , due to the increased complexity of the system and the low levels of traffic .