The dog handled himself remarkably well! Why the owner/handler called his dog's attention to the cat in the first place is beyond me! I think the dog should, and very likely would, have ignored the cat in that setting. Though it's hard to say. I know dogs seem to have very strong instinctual animosity for bears, I would expect a similar instinctual feeling toward a cougar. In any event, it was really sad that the owner didn't just allow the dog to handle the situation naturally, rather than teasing both the cougar and his dog!
On another note, I saw an Akita mix service dog, well over 100 lbs, while out shopping the other day! I was a bit shocked, as Akitas are not exactly known for their even, calm temperament! But this dog conducted himself really well, I was impressed!
It's not the size of the dog in the fight, it's the size of the fight in the dog. Mark Twain