Yeah, just like the post described - they know good and bad. They get sneaky, quiet and guilty because they know they were bad.

I have a cat and a dog and i swear to god, my cat gives me a challenging look of pure intent when she does something that she KNOWS she is not allowed; Like jumping up the kitchen counter. We don't want her on that. She sits in front of it, sees me coming, looks me in the eyes with a very certain look and jumps on it. When i tell her to jump down, she will do it immediately but again... a look of pure intent and naughtiness.