I had read this years ago but just recently thought about it because it was referenced in the book I'm currently reading. I thought then, as I think now, that it could very well be true. Give me a good schizophrenic any day over a sociopath or a psychopath, please. They have much better dreams, too.
Seriously though, it does come to my mind that if there are that many people without the spark that gives them empathy, it does explain the bankers.