This paragraph took my eye:
"Children pick up vast amounts of language as they go along. For instance, a child of two understands the phrase “I love you”. I don’t think Chaser would know that. By three, a child would say: “Mummy, I love you” and know the meaning. Chaser couldn’t do that.’"
I'd love to know how anyone can objectively test small children for 'comprehension of love' and compare against an animal that cannot actually speak any human language - whether or not it can comprehend it. Or any human, for that matter.
I feel that a test that can accurately tell you if 'I love you' is being fully understood and appropriately used would have *considerable* value on the open market.