Sleep is overrated?

"Sleep is overrated," one of my work colleagues frequently says, but I do not think that I agree with him. Superfluous sleep, perhaps, but not adequate sleep. "For so he giveth his beloved sleep," the Bible mentions, and if it is a gift worth thus mentioning, surely it is very important. We need enough of it. I suspect that if all Americans got at least adequate sleep, health care costs would go down.