It is not anticipated that the readers will have much familiarity with terms like "Monophysite" and "Eutychian". Furthermore, the expectation is that readers will be under the influence of the media and popular culture and therefore inclined to view orthodoxy as boring and heresy as exciting.
They will probably be surprised by the central thesis of the book, namely, that the Christ of the heretics cannot save us...and they are certainly free to challenge it. But those same readers will in turn be challenged by the compelling argruments advanced by C. FitzSimons Allson, retired Bishop of South Carolina in The Cuelty of Heresy, a very readable text of fewer than two hundred pages. The book's format is wonderfully well expressed and full of memorable examples and analogies from everyday life. (E.g., "the Appollinarian train carries only freight and not people, while the Nestorian train comes through the station but does not stop" for sinners, who must learn to run faster if they want to earn a place on board.)
The importance of an orthodox understanding of Christology and the Holy Trinity is that it points the way to God's saving grace. Both Adoptionism and Gnosticism are forms of spiritual elitism, and they are widespread today. Frequently, they mask themselves as true Christianity, deceiving many good sheep and not a few of the shepherds who are supposed to be guarding the flock.
Heresies are as real, relevant and dangerous as a flask of deadly poison. Bishop Allison demonstrates the cruelty of heresy and the vitality of orthodoxy, contending that heresy is essentially an error of the will whereas faith is a rectitude of the heart. What is perhaps most impressive is that he is able to do so in such a readable and engaging book.