Cribs from touch
"I think I read somewhere that elements of "personalisation" in the source messages did come into it. Each operator had their own keying style, so the interceptors knew who it came from, and certain operators would have little quirks in their message content."
Yes this was used to generate individual cribs:-
- Operators sending messages to be passed on to girlfriends etc
- Standard form test messages that they were too lazy to alter as they were meant to.
- Returned test messages to check for clarity of transmission and retransmission
- Requisitions of stores and stocks were another good one. If you got a message from a fuel dump they would report stock levels periodically at a known time each week etc.
- And the well known weather and HH (I don't even want to type those two words) cribs
And the list get pretty big but one you know the 'touch' of the operator you could look for a likely crib in the decrypts.
Obviously you focus on the operators who spew out cribs with standard form messages at known times.