Adam,
Thanks for giving this book and this concept airtime.
Le Griffe has been talking about this issue for years. I have been stating it in relation to Pareto’s work on the distribution of property necessary to organise voluntary production. And the usual suspects in IQ research have been concerned about it for decades now.
In my work – high trust societies – its almost impossible to form one if the distribution is either too low or too wide.
Politics in particular suffers since at every two standard deviations people rely on almost entirely different frames.
Lastly ( I have been giving talks in this lately ) the west may be the fastest developing because of our oath and our discovery of truth. But in addition westerners relied upon manorialism, prohibition on cousin marriage, delayed child birth, and hanging of .5-1% of the population for more than a thousand years.
So our success has just as much to do with our aggressive genetic pacification as it does to our institutions of truth, oath, jury, property, and common law.