[taneq]

The twin studies suggest that you can "break" your kids (and damage their outcomes to some degree) if you go too far in most directions, but that as long as you don't do this and you stay fairly moderate, their outcomes depend far more on nature than nurture.

In the case of tiger moms, the confounding factor is that along with their overbearing parenting they probably passed along some highly effective genes, though the kids probably would have been just as effective (maybe even more-so) with a more relaxed upbringing.