[taxcontrol]

Not if the operators are sloppy. One of the techniques employed by the Germans with Enigma that lead to the down fall of the crypto method was to transmit a 3 letter designation of the transform set, followed by the same 3 letters at the beginning of each message.

In short cryptography is no stronger than the weakest link... many times, that is the operators.

[LibLieSlayer]

True enough.

LLS