Having followed Mr. Strieber's career and writings since Communion, I believe the former. He is being as honest as it's possible to be in telling a difficult and strange story.
Solving the Communion Enigma is Mr. Strieber's summation of the journey that began for him with the Communion experience, which was an apparent abduction by alien beings on December 26, 1985. While his relating of that event led to him being identified with the popular notions of "alien abduction," he has never been an adherent to that interpretation of what happened to him. He does not dismiss the possibility completely because he finds value in keeping the question open, but he does not aver that his visitors were from another planet. In Solving the Communion Enigma he says, "Being identified as a believer in aliens has always troubled me. It just doesn't seem to me to be the only possible explanation."
Another famous UFO researcher, Jacques Vallee, came to a similar conclusion in his book, Dimensions. After relating some of the more exotic of UFO anecdotes, he describes the logical expectations of alien visitations and concludes that "aliens from another planet" just isn't a strange enough explanation for the UFO phenomenon.
So what is? That's the question Mr. Strieber has been trying to answer, or at least address, in the years since his Communion incident.
Solving the Communion Enigma is a record of Strieber's years of engagement with the phenomena. Followers of his writings, in both his nonfiction books and on his website (www.unknowncountry.com), will recognize much of the material and be enlightened from his further observations. They begin right after the Communion incident, when Strieber sought to engage the beings that assaulted him that fateful night. Or maybe I should say he continued to engage them since he later came to believe the contact started in his childhood. He describes this in Part One and advances the theory that childhood traumas, whether by chance or manipulated, can open a person to this contact.
It can also open a person to invasive trauma, like having objects implanted in their bodies. I was aware that Strieber had claimed to be the recipient of such an implant and had even tried to have it removed, but I had not read about it in detail. He describes what implants are and relates his own experience in Part One. It is fascinating material and I can see why the study of such implants would be a way to bring a scientific angle on the abduction phenomena, if any credentialed scientists would do it.
I had also not read much at length about crop circles and he has a section in Part Two about that. Like implants, there's more to the subject than I realized and it would be worthy of real scientific study if it were allowed.
In Part Three, Strieber gets more into his personal experiences with beings that might be alien, or humans from a different plane or state of development. His experiences are in keeping with much mystic lore, both modern and classical. His descriptions of his times of meditating with these beings, the symbolic insights they offered, and the richness of his time with them are fascinating. His premiere experience of this kind was with the "Master of the Key," an apparent man that he met in Canada and conversed with in the early morning hours, gaining insights he related in his book, The Key.
Strieber relates all this other-worldly material in tight, engaging prose. Reading his work is like listening to an intelligent and experienced dinner guest talk about exotic, engrossing subjects, who is also not afraid to let some emotion come through. In fact, he relates some really personal things. But that too, is typical of his writings, and a testament to his honesty.
Early in Solving the Communion Enigma Strieber says "Something about this world of ours simply does not add up." Many agree, though what in particular about the world doesn't add up is a matter of considerable argument. Pet doctrines that adherents can't bear to see contradicted fill the gaps in our knowledge and offer the solace of ignorance to true believers. But UFOs and the phenomena that surround them are notorious for contradicting reality as we know it, and laying waste to theories that seek to explain them. They deny themselves even as human authority denies them, and other factions embrace them as real space aliens. Experiencers, like Mr. Strieber, are caught in the middle of these extremes and are alternately lauded and hated.
Yet it is this very tension that may be the whole purpose of the UFO/alien abduction experience. Trying to understand the contradictions and the positive and negative passions they arouse may be the force exerted by the intelligence behind the UFOs to actually change the way humans think. As Mr. Strieber says, it may be the very force of evolution as applied to humanity.
If so, then finding a productive way to engage the UFO phenomena is one of humanity's greatest quests, and Mr. Strieber is a pioneer in trying to show us the way. Solving the Communion Enigma is a very helpful tool towards reaching that engagement.