Personal - Interesting

This strongly reminds me of “known plaintext attack”, but I'll bite. I know you couldn't care less, but here what a “known plaintext attack” is: suppose Alice corresponds with Bob over a secure channel. Eve (the evildoer is female. That's a very old axiom — even 3,000 years ago, men knew that girls are evil.) wants to eavesdrop, but can't break the cryptography in reasonable time. She tells Bob something that involves a certain word or expression that is very hard to rephrase, that she thinks he'll tell Alice about. Then, she can bet that word or expression is included in Bob's next transmission to Alice. Trying to decipher the message by guessing which part of it is the known expression and seeing if a key successfully decrypts it is order of magnitude easier than deciphering it with no known data. This is my CO discussing his job.