[TeMPOraL]

> I have a hard time squaring a lot of the hard and fast rules against my own experience.

I think it's the same thing like in other self-help sub-genres: any of such hard and fast rule will work very well for some people in some situations. That's why there are so many of such rules, why they're often mutually conflicting, and why they all have armies of evangelists behind them.

> Certainly one persons life can’t detract from large scale statistics.

Conversely, those statistics talk about what's average, typical. Some things have high enough variance that even most solid RCT only works as a guideline for policy at scale.

I have only two children, but it's clear to me both develop according to completely different trajectories. It kind of makes sense as, even if us parents didn't change in any way, and the environment stayed constant, our younger daughter is still spending a lot of time in the company of her sister. That's a huge additional high-variance input source :).