Okay, here we go....
In the introduction/acknowledgments, Adams clearly states that Hatsumi is the 34th Headmaster of Togakure Ryu, Okuse is the mayor of Iga-Ueno, and a scholar and historian. It has been long established that Yumio Nawa is not a Ninjutsu practitioner, but is also a historian. However, he is an instructor, or the head of Masaki Ryu Manriki Gusari Jutsu (which he taught to Hatsumi in the 50's or 60's). Iga-Hakuyusai is a performer, and that is simply a stage name. The only other verifiable (although a bit contraversial) authentic Ninjutsu practitioner mentioned in the book is Seiko Fujita of the Wada-ha Koga Ryu.
You're right, Emilio, the term Taijutsu is not used in the book. Instead, the term Kumi-Uchi is used, a term which is (or at least, should be) familiar to all practitioners of Ninjutsu. The term simply means Close Quarters, and is used by a variety of schools, sometimes to describe a grip (Takagi Yoshin Ryu, Koto Ryu etc), and sometimes to refer to a form of combat (Yoroi Kumi Uchi from Kukishinden Ryu, sometimes used instead of Dakentaijutsu) which could be purely unarmed, grappling, striking, using small armaments such as kabuto wari and daggers, armoured or suhada (unarmoured). The use of the term depends on the school, the particular head (Gyokko Ryu has been known as Ninjutsu, Ninpo, Shitojutsu, Kosshi, Kosshijutsu in it's time, depending on who was heading it), who it is being described to, and sometimes, just which term a listener decides to latch on to. But, yes Cryo, the term is sometimes used to decribe a particular schools curriculum.
Remember that many terms are used within Ninjutsu, such as Koppo, Kosshi, Dakentaijutsu, Jutaijutsu, Yoroi Kumi Uchi, and Ninpo Taijutsu, so which did Adams choose for convenience? This, by the way, is not unique to the Ninjutsu schools. Yagyu Shingan Ryu has several terms used, depending on whichsection you are studying, if it is armoured or not, and the level of experience the student has. These terms include Katchu Yawara, Kogusoku Yawara, or Suhada Yawara, and these are further split into Torite No Jutsu, Totte No Jutsu, Kogusoku Totte, and Gyoi Dori (a particularly fascinating area from my perspective...) The term Kumi Uchi is used specifically by schools such as Hoki Ryu, Takenouchi Ryu, and Enshin Ryu to name a few.
Finally, Adams' book is considered a seminal work in that it is one of the primary sources for what was known as the Ninja boom of the 80's. It is the first book I read on the art, and willl always have a place on my bookshelf for that reason. But it is simply not an accurate portrayal. Adams needed to have a number of sources to be taken seriously, and that meant some people had their status raised to add credibility, not a totally unheard of situation. Hatsumi, Takamatsu, and Seiko Fujita are the only people whose actual claims are listed, that is your first clue as to the status of the rest (who, I might add, I do have a great deal of respect for, particularly persons such as Yumio Nawa - who, if you ask him, will simply tell you he has never trained or taught Ninjutsu) as definitive sources. Adams was also one of the first Westerners allowed to watch the training by Hatsumi, but he never trained the art. Without that experience, sitting and watching doesn't add up to much.
If Adams' book is what you are basing your ideas on, you're a bit behind the times. As I have previously said, you really need to allow yourself to accept that you don't know everything, and open your mind to the idea that you have a lot to learn. So stay, and learn form those who have been there, or don't be here and stick with your fantasies.