According to the book theories, your real intent in commenting (as revealed by the way you framed your remarks) is that you wanted to validate your self image of being an expert on animal behaviour, having raised plenty of dogs/cats.
One of the main thesis of the book is that metacommunication is an automatic mechanisms which is used by humans as a sort of sonar signal: every time we communicate with other we are sending out an image of what our self image is, hoping that their reactions will validate it (e.g. "I am trying to look cool, or learned, or authoritative or whatever, and I hope that the way you react to it confirms that my signal was received)".
In a discussion about a Pscyhology book (by a quite influential and respected researcher) you felt you really had to make known to everyone that your superior experience as breeder of innumerable dogs and cats made amply clear that the guy was a charlatan, due to a half-page example from a 304 pages book.
A book you have not read, and you probably did not even know it existed before another random guy mentioned it.
From this I infer that what you really wanted to say is "Hey, look at me: I know lots about cats and dogs."
I am not blaming you. This is exactly what Watzlawick considers to be one of the primary "uses" of metacommunication by humans: a way to project our own self image on others.
And I am surely doing the same, just like everyone else. Maybe I am a bit more conscious about this phenomenon, thanks to having read the book. ¯\_(ツ)_/¯
This isn't a good pitch for getting me to read the book. Seems like too much psychology being applied where it's not warranted, possibly leading to misunderstandings of sitcom proportions.
I knew someone who couldn't smoke weed because any time she did, everything seemed loaded with intent and backstory that seemed all too true.
Communication doesn't happen in a vacuum. I hope the book at least acknowledges that metacommunication received is subjective to the receiver.
