This is utter bullshit. There have been experiments who prove this does not work. Absolutely no scientific experiment was able to confirm this method works.
US Army
Italian Air Force
NASA
... and many others
Have conducted tests and all got to the same conclusion - it does not work. They proved you can break up 8h of sleep into multiple segments and sleep in 2 hour segments several times a day. However you HAVE TO have a total of 8h/day of sleep of your mental abilities drop. You can stay without 8h/day of sleep but you will be a zombie and the whole purpose of you sleeping less is defeated - you will have several extra hours but you will struggle to perform the most basic tasks.
Sleep deprivation is a form of torture, used in interrogation by police and intelligence services. It negatively affects growth, healing and lots of other physiological aspects.
It has been proven however that sleep helps a lot with obtaining better focus, attention, healing, etc. As a matter of fact I remember a TED talk where the speaker described in detail how beneficial sleep is.
Only positive effect of sleep deprivation is regarding people who suffer from depression. 24 hours without sleep will counteract depression immediately, however they will always experience a relapse of depression the instance they get enough sleep. In other words after a night of sleep, they will be depressed again.
I have personally tried this uberman method. There are actually multiple multi-phase sleep methods - this being the one with least sleep. These are my findings:
- Impossible to have a social life - since you can't stay awake for many hours in a row.
- Extremely difficult to accommodate to. It will take you days to teach yourself to fall asleep immediately and by that time you will feel like a walking zombie because you will have to suffer serious sleep deprivation in order to reach the state where you fall asleep immediately so many times a day.
- You will not wake up. After the sleep time ended, you will fail to wake up. You will maybe at first but after a while you will not hear the alarm and if you will hear it, your brain will not identify it or just completely ignore it and you will sleep a lot more.
- You micro-sleep. Micro-sleep phases are periods of time between several seconds up to several minutes where your brain automatically shuts down. You can not control it. You will fall asleep regardless of what you are doing. You will fall asleep sitting up and you will not fall. But you will sleep. Micro-sleep doesn't occur a few times in a day. It occurs a few times in an hour. In other words the amount of micro-sleep you will get in a day will sum up to hours. And the rest of the time you will be a zombie. So you will go from 8h of sleep to 24h of being in a "coma".
- There is no way to work after a couple of days because:
- You can't focus
- You take the wrong decisions
- You "run in circles"
- You forget the most basic things. If now you were in the kitchen and thought "i should make that link red" by the time you get to your PC you will forget you ever had that thought or you were in the kitchen.
- Simple tasks will become impossible. A mathematical operation that is not as simple as 2+2 will seem to be impossible to solve. 17498*2496=? using pen and paper => you either can't do it, you do it but is wrong or you just feel mental pain from even trying. 12*9=? in your mind => impossible. You ill struggle to remember ho much 2*9 is and then you will struggle to decide if it really is 18. Your girlfriend called you to buy bread? By the time she gets home you will barely remember you even talked on the phone. No bread tonight.
You want to sleep less and work more in front of the PC? It's impossible. The only way to sleep less and have energy requires you to stay most of the day under natural sunlight. It works. If you stay 10h or more in natural sunlight (summer time) you will be able to sleep less and have energy. However you need the sunlight factor for it to work and you have no sunlight in front of the PC.
What you eat, what you drink and how you live has a major impact on the amount of sleep you need. If you have a very healthy life you will feel great. Otherwise you ill feel like shit and your body will need a lot of sleep to compensate for the abuse it is subjected to.
I am not saying it is impossible. I am saying the vast majority of people can't do it and those who can, do it because of other reasons - autosuggestion, sunlight, healthy lifestyle, a serious need (life-threatening situations) that produces a fight or flight response (Adrenaline rush), etc.
Also there are people with medical issues that naturally sleep less. It is how they are built personally. There's a name for this but can't remember it. Old people sleep less too - my grandmother slept 4h/night but then again she didn't do much during the day either, wasn't overstressed, had no physical workout, etc.