That's quite clever. In crypto literature, I guess it could be called like "covert cross-channel".

It turns out that the idea itself of communicating secrets in plain sight is called "subliminal channel" [1], which differs from steganography (hiding a message inside another message).

My question is not meant to imply conspiranoia. It's whether we as an audience of online forums have been fooled by this technique at some point.

[1] https://www.emsec.ruhr-uni-bochum.de/media/crypto/attachment...