Well, here's my take on it. I must admit I have never read the book, but from your comments this is what I think:
I have two very strong willed children under 5. My son is oldest and will be 5 next month (although you'd think he was going to be 35). I do not believe that a child this age can make BIG decisions about disciplining themselves only because they have no life experience to lead them on. Now, I do discipline my kids and TEACH them about right and wrong, BUT I am sure to make their options known. What I mean to say by this is: My son get's disciplined when he does something wrong, but he is very award of the consequences before he does this. For example, he loves to cut things with sharp knives, however, he knows that first he must ASK. His choices are: Get in trouble for not asking, or potentially cut his finger. He has done both! Now, this is not to say I let him "do what he wants", but you can only tell a child for so long, "don't touch the stove" and eventually the just need to get the concept that the darned stove is hot!! Now, how in the world to you explain "HOT" to a child that has never been burned?? You can't!! Just like you cannot explain the concept of child birth to a MAN, unless they have done it, they will just never know.
Now, other ways I do get my children to think for themselves? "Mom, how does this work?".... Me: "Figure it out... look around.. do you see a plug.. a switch... does it have batteries?" Then I make then LOOK at it for a moment and I walk away. This, believe it or not, REALLY works. They will sit down and figure it out. My daughter is afraid of spiders (shes almost 3). She screamed once and I picked up a stick and scraped away the spider web and then said "spider is gone" and walked away. Now, when she screams, I tell her to take care of it herself. She will search for a stick, broom, rake or whatever to handle the situation herself, she no longer wants me to take care of it. She thinks for herself, but, at first, someone had to give her an example of how to deal with this situation.
Now, with all this being said, I do lay off "external direction" per se to let the children learn for themselves, but they do still need guidance to determine the right directions to head. You cannot effectively parent (in my opinion) by just letting them fend for themselves (at least not at this young age) and where are they going to get examples from if you don't give them to them. Children need to be disciplined but need guidance to determine right from wrong, once they know, they can be expected (within reason) to make choices from there on their own and deal with the potential consequences, good or bad. This in and of itself is a learning experience and a method of discipline.
I hope this isn't confusing you, but it's my take on things.