Ok, self-evident is the wrong word. Properly expressed, what they describe and conclude is exactly what I have experienced all my life. If I stay up all night, or close to all night, the following night I will sleep for 10+ hours. The following night after, another 10+ and the 3rd night 8-9. Not by choice, I just can't be woken by my alarms.

This pattern repeats almost without fail.