"The point is to capture as much data as possible with minimal or no clipping. Then in post, you are free to manipulate that data as you see fit."
That is exactly correct. If you have NX2 you can easily demonstrate this. Load a nicely exposed NEF file and play with the various Picture Controls in the Develop section. You will see that Neutral yields a histogram that is rather bunched up as compared to Landscape which yields a histogram that is more spread out.
Furthermore, as you compare Neutral to Landscape, you will notice the histogram data moves slightly to the left. You can also see this by clicking Double Threshold and noticing items at the white points do not change as much as those at the black points.
What does this mean to me? (I almost always set Picture Control to Neutral.) After an exposure, I first check the "Blinkies" and then the left side of the histogram. If I have blown out any important detail and I have some room on the left side of the histogram, I will shoot again with less exposure. If there is no room on the left side of the histogram, then it is time to consider HDR processing.
I am confident during post processing that I can properly display (print) all unclipped data from a raw file displayed by Neutral Picture control. However, with Landscape Picture Control, for example, there MAY be clipped data that can be recovered, but I can't see it and cannot be sure because it has been pushed off the left side of the histogram.
In any case, your selection of Picture Control options available in the camera does not change the raw data. It only provides options for displaying the data.