Don't know why you're being downvoted. As a parent, every single time I read something about 'raising your kids X', Dr. Lipschitz (from The Rugrats) comes to mind.
I would say that, no, parents should not be expected to internalize all of the thousands of different things we're finding out about the best ways to raise kids. It's far too much to know, and the knowledge is currently too tentative. But, it's also pointless to bring that up every time a new study comes out, because these things are good to know. That's probably why the GP is catching downvotes.
I've seen how parents can get amazingly OCD with these studies. They'll form cliques and look down on parents who don't perform what the current best practice is. Because of that, I think it always bears repeating.
Probably because most of this is common sense that you do anyway. Generally speaking, you don't tell you child that he's and evil human being because he didn't pick up his toys.
But you want a kid to self-identify as a "good" person, and do what good people do. For most folks, this stuff either happens pretty naturally, or the parents adapt as their kid learns how to game them.
http://www.newyorker.com/online/blogs/shouts/2014/03/new-par...