Having listened to Dr. Mark Hewitt on numerous occasions, it is refreshing to hear a level-headed approach to the Zodiac case using police reports, FBI files and documents from the standpoint of impartiality. Dr. Mark Hewitt is an intelligent and thoughtful individual, taking a reasoned approach to the available evidence gathered thus far.
However, in the prelude to the final book of the series, he states "definitive evidence of the killer's identity." 'Definitive' can be described as reached decisively and with authority- and while I would take note of Dr. Mark Hewitt above most, he is not the first Zodiac researcher to claim such a discovery. The trilogy is certainly striving for a conclusion, having hunted and profiled the confirmed murderer of five in the previous two instalments. Whether an answer to the Zodiac case is required upon conclusion of the trilogy, is debatable, and dependent on the reader.
Putting aside the current DNA research into the case, I have yet to see any definitive evidence or scientific breakthroughs to conclusively pin down any suspect to the Zodiac Killer mast. Many excellent researchers have come and gone, and while plenty have advocated for a particular suspect, none have achieved even a general consensus within the Zodiac community. This bears testament to how the 'evidence' can be manipulated to reach the conclusion you were originally looking for. This has been achieved, not only in shaping the case around a suspect based on cherry-picking the evidence, but also by finding the suspect's name in the ciphers through less than compelling reasoning.
Dr. Mark Hewitt states of the Zodiac that he will "name him directly," but, whether such a bold statement holds any sway with a tired and weary Zodiac audience, who have heard such proclamations innumerable times before, we will have to wait and see. I wish Dr. Mark Hewitt every success in his final offering, and have no doubt that it will be a thoroughly well researched and informative addition to the Zodiac mystery. However, my guess, is that the "killer named" in 'Exposed-The Zodiac Revealed' will certainly not close the book on this case any time soon.