Jumping in here a little bit late, but my experience has led me to shy away from using ADL in camera and only apply it in post if needed. I like the way 99% of my images come out of the camera without ADL and turning it on often times creates problems in the image (to my taste)
Sometimes however I'll get a very contrasty image that looses shadow definition or is maybe a little to "hard" for my tastes and adding ADl in NX2 post will fix it for me.
I've never done extensive testing as Eric did but it's just from my observations of what happens to my images.
All of this testing and reporting has made the process clearer in my mind and I'm sure I'll think about it more when making a shot or working post.