Reading this article was oddly reminiscent, as he sounds like me when I was younger. In fact, I can seem to relate to a large portion of the article. Let me try and shed some light on several points:

His gaze settled on Allan. Grabbing a wooden chair, he hoisted it overhead as though to do violence but paused for several seconds, giving Miguel a chance to yank it away.

Right - first, psychopaths (let's just call it that for now) absolutely understand reward and punishment. The question, however, becomes more "can I avoid the punishment?" rather than "oh no, if I do that, will I be punished?" It's not entirely conscious - it's natural. Maybe this only happens with a certain degree of intelligence, but if his parents made it clear that he'd have no way of weaseling out of a punishment, and would be caught for sure, then it would deter his behavior. That is, of course, unlikely. His parents are emotional, and I'm sure he knows it. Either that, or the punishment just isn't affecting him. He just screams and pretends, so they won't try something new. All tactics I've used. He realizes that if he throws the chair, he will ACTUALLY get in trouble. He just wanted to get a point across. He overreacts, and his parents respond accordingly, and lectures his brother. Win-win.

Some, including Michael, were actually worse; one had begun biting the counselors.

This is probably misrepresented. When a kid throws a tantrum, often the counselors will try to restrain him. Yes, this happened to me (twice). If the kid cannot use his arms or legs, it should really be expected that he's going to bite. He believes he has a logical reason for throwing a fit - restraining him isn't going to change that.

Coldblooded, callous-unemotional children, by contrast, are capable of being impulsive, but their misbehavior more often seems calculated. “Instead of someone who can’t sit still, you get a person who may be hostile when provoked but who also has this ability to be very cold. The attitude is, ‘Let’s see how I can use this situation to my advantage, no matter who gets hurt from that.’ ”

I'd argue that psychopaths have both 'hotblooded' and 'coldblooded' elements. Which they display at any given time, is simply a question of which has the most reward. If the situation is hopeless, even the most hotblooded psychopath will return to being coldblooded. They'll probably never swallow their pride, but they'll win, one day. The trick is understanding their logic - because their logic is more cause-effect, than reflecting on societal norms we've grown up with.

So they don’t develop the same aversion to punishment or to the experience of hurting someone.”

That's not true at all. My parents used to beat me (Chinese family, accepted norm) when I threw tantrums and did something wrong. I used to hate it, but I doubt I would've grown the same way without it. Rather than having to form my own mental punishment, I could relate "if I do this, I'll get beat". Then the question became, "is it worth the potential of a beating, and can I prevent them from finding out?" Psychopaths understand punishment just fine... at least intelligent ones do. When I entered high school, however, I found out that any suspensions go on my record for University. I also heard that good universities don't accept people with bad records. I was suspended over 50 times in elementary/junior high, but since high school, I've had excellent behavior. It's easy to trick your parents into thinking you're remorseful... it's harder to convince an organization that deals with thousands of applications.

In another study, the researcher Mark Dadds found that as C.U. children matured, they developed the ability to simulate interest in people’s feelings.

It's not just simulating interest - it's simulating emotions altogether. It was difficult as a child, but over the years, I've learned what emotions are supposed to be, when people display them, and what degree they should be displayed. Hence, if a psychopath starts to live two different lives, they can easily switch between different levels of emotional display. It makes adaptation a lot easier, and people don't really consciously notice.

It's like programming. if(situation) { respond(situation.severity)} Eventually, you get to see enough situations, and can extrapolate responses for situations you haven't seen. Once in a blue moon, you're completely off. That isn't to say ALL emotions are restricted. Shame, guilt, fear, sadness, and love may be difficult, but happiness, boredom, and anger come easily.

All in all, I feel people really misunderstand psychopaths. If you're a parent, and have psychopathic children, find something they inherently cannot live without, and threaten it. Beatings may work, but it's not fool proof. You can't starve them, because they realize it'll hurt you more than it'll hurt them, and mutually assured destruction (up to a point) is acceptable. Remember - it's not how they inherently behave. It's how they behave, given the circumstances. Instead of trying to fix the root problem, go after a symptomatic treatment. Just because they misbehave, doesn't mean they won't be productive members of society later on.