I also found the book 'Selfish reasons to have more kids' interesting on this topic. It uses twin studies to suggest that although parenting does have an effect in the short term, in the long term genetic factors are dominant as long as the child is raised outside abject poverty.

The conclusion of the book is: provide a healthy environment, but don't agonize over violin lessons and other 'enriching' activities.

That said, I went and bought another book with advice on how to talk to your child to stimulate language development ('look who's talking') and we read to him a lot. So, I believe the twin studies in theory, but not in practice.

Finally, on this general topic, 'how children succeed' points out that character traits like grit (willingness to keep trying something hard and unpleasant) and conscientiousness (desire to do the right thing) are more important than intellect in success, beyond some modest intellect baseline. I suspect my son is plenty smart, but what really interests me is trying to foster grit and conscientiousness.