I realized today that a common science belief is bullshit.
I semi regularly see articles noting that in the middle ages people slept in 2 chunks instead of one long window like we do now. There is plenty of written records to support the history. They say this shows we are meant to sleep that way and it is better for us.
They are wrong. Another fact about the middle ages is that everyone drank beer all day every day. The water wasn't safe so it was the only option. Fun fact about alcohol, it is a sedative but digesting it creates a stimulant. That is why you black out then wake up 4 hours later.
Split sleep isn't the natural state of man, it is the natural state of drunks. Functional alcoholic is not a desired state to emulate for optimum human performance.