I recall seeing studies making more concrete claims about burnout, overtime, etc, which seem more like what you were claiming. I can’t do more than google randomly for such studies at the moment which seemed less useful. I also don’t recall those studies matching the claims about 4 hours in particular.
(That said, another source of the four-hour thing is the book Peak, which claims you get four hours of deliberate practice a day, which is a somewhat different claim)
Nod.
I recall seeing studies making more concrete claims about burnout, overtime, etc, which seem more like what you were claiming. I can’t do more than google randomly for such studies at the moment which seemed less useful. I also don’t recall those studies matching the claims about 4 hours in particular.
(That said, another source of the four-hour thing is the book Peak, which claims you get four hours of deliberate practice a day, which is a somewhat different claim)