As you've said yourself, the Essentials books were designed to be the new onramp to D&D. Where did you think that onramp would go? Of course the stated requirements going forward would reference HotF* and the Rules Compendium. That doesn't address the utility of the product for those who only have earlier 4e books.
I thought that was obvious - the on-ramp was supposed to lead players to buy the Traditional 4E products, because the Essentials line was proclaimed to only be series of ten products.
Ah, but now you're backing away from what you've said before, which included "...this book offers nothing but a few pages of fluff material about the Shadowfell, and very little else.", and (on the Neuroglyph Games site) that this book "was designed entirely as a D&D Essentials book, and does not have any purely Traditional 4E content in it at all!", and that "WotC has made it clear that it no longer has plans to support new products for Traditional D&D", and, in response to WotC folks saying that the book would contain support for "Core" D&D players, that "I am particularly angry at having been blatantly lied to by Wizard of the Coast.". Those are not statements that support what you just said in the paragraph above; they imply that if you didn't buy either of the HotF* books, that Heroes of Shadow is completely useless to you.
No, I never implied that at all. They are statements I made about being angry at WotC for marketing the book as a "Core" product, and then presenting a book with Essentials-exclusive content (Classes/Domain/Schools) on over half its pages, and with no content that one can label as exclusively Traditional 4E. You can still use content from this Essentials book in your 4E game - as you can with all Essentials products - but that does not make the book a Traditional 4E product. Using your logic, one could argue that because you can use feats and powers from HotF*, that it is not an Essentials book but is really a Traditional 4E book.
Ask this question: If you didn’t buy any of the Essentials products, what could you use from this book? Almost everything. AFAICT, other than the warpriest Death domain and the two new mage schools, this entire book is directly playable by someone who owns only the Player’s Handbook.
Alright, I have a counter question: Why is it so difficult for you to admit that this book, which contains copious amounts of exclusive Essential material is really an Essentials book? I have already admitted that Essentials material can be used in Traditional 4E characters, so calling
Heroes of Shadow an Essentials book makes no difference, correct?
In reality, making that admission makes a BIG difference - because the moment you admit that this book is an Essentials product, and not a Core product, then you would have to accept that WotC mislead the D&D community about the nature of the book. And WotC even went so far as to mislead the D&D community about the Essentials line being an "on ramp" or "gateway" to the game - it has become the replacement design paradigm for all future releases.
Is the fact that Essentials is the new paradigm for future releases a bad thing? Not necessarily - the poll shows that there are more people enjoying pure Essentials and Essentials/Traditional mixed content than those just enjoying Traditional content.
Is it a bad thing that WotC misinformed their customer base about the true purpose of Essentials to become the new design paradigm? Yes - honesty is always preferred - the gaming community should have been told about the impending change, rather than be misinformed and lead to believe that Essentials was designed to merely assist new players.
Does this make Heroes of Shadow a bad book? Nope, it's a great book, but players and DMs wanting a non-Essentials play experience will need to consider purchasing this book carefully, given the amount of exclusive Essentials material it contains.