I thought the 64 DCNH subtypes were sufficiently (and probably consistently) described for me to now say that the DNCH subtype system is meaningful (probably more meaningful than the enneagram, although determining a DCNH subtype for myself is perhaps not as interesting as attempting to find which enneagram type I am, because the DCNH subtypes are variants of the Socionics types).
I still would not recommend the DCNH subtype system to someone new to Socionics, but I think the 16 type descriptions combined with the 4 DCNH "flavours" for each type will give anyone a good sense of the range of a type's natural behaviour.
If I'm EII, then I'm most probably the N-subtype, with the C-subtype being a somewhat distant possibility. It seems that if I'm ILI or LII, I'd probably be the N-subtype of those also. When looking at the ILI description as a whole with its other other DCNH subtypes, I thought that the ILI personality is contrary to how I am overall. With LII, it was not satisfactory at describing me on the whole.
Unless you fundamentally disagree with the concept of the DCNH system, 80-90% of the book is probably uncontroversial (to those who might be worried that it is too heretical or abstract). I think the DCNH subtype as described has some use, although I'm doubtful that it could be used much beyond self-typing (but perhaps only because determining a self-typing and a typing for others with the 16 types is typically problematic enough: the four DCNH subtypes may inform you for future usage however and I will try to bear them in mind in future). I disagree with the questionnaire limiting itself to only two options per question, but that is only a small part of the book which has a few wondrous things.
I thought the book was well-written and better than Filatova's in terms of content, and I'm happy to recommend it.