Kind of a tenuous argument. Yes, some famous people do it now - but you could as well argue from, say, the Paris Review interviews that because so many great writers write first thing in the morning, you want block sleep so you don't get up late. It may also be natural, but lots of things are natural and don't cause greater creativity. And one may be able to cite personal anecdotes, but the causation could very easily be the other way: someone gets up because they have a burning idea, not because they got up and then also had a breakthrough. I think it would be much more compelling if they could point to even basic experimental verification; for example, showing greater solution rates to 'insight problems' in a segmented condition.