I'm much more interested in why a body needs an amount of sleep, what processes it is conducting, and how you can affect those processes.
What happens in the 7th hour that didn't happen in the 6th? If it's a fourth REM cycle, why do we need 4? What does the fourth do that the third didn't? Why do REM cycles take that long? Can you make them take more or less time? Can you determine lack of sleep from a brain scan? Can you tell the difference between a 6th hour brain and a 7th hour brain? Does anything you eat or do during a day affect how long this process takes? What about hydration / nutrition?
I'm sure these are all answerable, but I'm not sure most people know the answers, and this article certainly doesn't get us any closer to understanding.
This article isn't exactly a presentation of research. Several of those answerable questions will probably be worth Nobel Prizes for the people who can answer them. This is fundamentally a puff piece with a sleep expert promoting his new general audience book on sleep health (Not discounting the tips, or his expertise, but this is obviously not a research paper). Several of the sleep hygiene tips he gives are things that aren't really settled AFAIK in the field, possibly why he even specifically mentions "practicing what he preaches" in that last question. He's preaching at least as much as talking about settled science.
What happens in the 7th hour that didn't happen in the 6th? If it's a fourth REM cycle, why do we need 4? What does the fourth do that the third didn't? Why do REM cycles take that long? Can you make them take more or less time? Can you determine lack of sleep from a brain scan? Can you tell the difference between a 6th hour brain and a 7th hour brain? Does anything you eat or do during a day affect how long this process takes? What about hydration / nutrition?
I'm sure these are all answerable, but I'm not sure most people know the answers, and this article certainly doesn't get us any closer to understanding.