Except that...
Those NDL dives with the same deco have been extensively studied with many test subjects and peer reviewed articles. That research indicates that the stop is not really necessary, but it can be helpful. It is not necessary because the diver has not built up enough of a nitrogen load to need more than that. Divers can be very confident that what they are doing will work.
In contrast, the decompression diver knows he or she has built up enough of a nitrogen load to form a very real danger. In order to deal with that danger, the diver follows a very precise protocol, a protocol that is highly theoretical and has not had anything like the testing for NDL profiles.
There are all sorts of theories, and they don't agree. Two different divers following the same bottom time profile will use different decompression schedules, and neither one has been more thoroughly tested than the other. Some of the most popular decompression systems being used today have been barely tested at all.
This past October my buddy and I followed the exact same profiles through three days of decompression diving, and we talked openly and with some concern about the theory and the lack of testing for what we were doing in our planning quite a bit. The next day I felt great, better than I have felt after such a series of dives ever, probably.
He was in the chamber.