"Not all cats, however, are in on the ruse: "It seems to most often develop in cats that have a one-on-one with their owners rather than in large household where there is a lot going on and such purring might get overlooked," she said. "Meowing seems to be more common in these situations.""
Gee, you think? Animal training is, in general, about understanding the basic nature of the animal, and working within those characteristics, whilst simultaneously providing (hopefully) positive feedback based on what the animal is doing, when the animal is doing it. All our home-grown barn cats "speak" the same language. The ferals we've taken in don't do very well ... The home-grown cats don't like the "different" way that the ferals communicate.
Same for the dawgs & horses. Our home-grown critters don't trust the newbies until they come around to our way of thinking. And no, force & violence aren't an option on our ranch ... it doesn't work in the long haul.
"House cats the team studied also apparently had a tendency not to perform when strangers were on the premises. "Cat's exhibit this behavior in private with their owners, typically at anti-social times, such as first thing in the morning," McComb said."
Bullshit. It's not the strangers, it's that the owners are acting differently. If you keep it consistent, the animals will react EXACTLY the same, regardless of who is in attendance. Animal training is kinda like buying property ... Consistency, consistency, consistency.
 Most animals don't actually think the way you and I do ... rather they are genetically programmed to react to a given situation. Real animal trainers take advantage of the human's ability to think combined with knowledge of the critter in question's natural instincts.
 Dogs & horses are owned by the pack/herd leader (that's us), and they like it that way. Cats are solitary; they'll allow you to feed them if they like you and how you treat them. They move on if you put a foot wrong. Nobody has ever really owned a cat.