Responding to both of the above at once, the reviewer is advising Dennis how to make his case even stronger, but the suggestions only confused the reader (us) even more. Thus, I think his advice can be safely discounted here.
Hitting two at once again, I think we have to ask ourselves who is the intended audience, and what were the authors' goals. (Luckily, we have one of the authors available, so I invite him to correct me where I'm off base.) In my view, the audience was not theologians or scientists, but the person in the pew, as Christy put it. We therefore should not criticize the book because it was a popular treatment of the subject, not an academic one. We also shouldn't criticize the book because it addressed the most popular form of the average person's beliefs about "historical Adam." Two-thirds of Evangelicals disbelieve evolution. The vast majority of them hold opinions similar to what McKnight describes, even if professional theologians and scientists do not. If your goal is to persuade the average Evangelical, then you must address their beliefs, not those of some other group (i.e., professional theologians).
I agree that we should not caricature or ridicule the views of those with whom we disagree. It's dishonest and counterproductive. Nevertheless, I agree with Christy that McKnight has not misrepresented the "baggage" that the average Evangelical attaches to Adam. For example, here is the first paragraph of the review of Adam & the Genome that you linked from the Gospel Coalition:
"I believe I’m genetically descended from Adam and Eve, but not just me: every human being can trace his or her lineage through Noah’s family all the way back to this first couple. I also heartily confess the doctrines of the fall and original sin, with Adam at the heart of what went tragically wrong with humanity. I would even say we misunderstand how Jesus put things to right, and what he did on the cross, without taking the full measure of this backstory."
At the least, he affirms #1-4 on McKnight's list, and there is no question that he believes that one cannot understand Jesus' work on the cross without affirming the "full measure of this backstory," which is a fairly strong indication of how he feels about #7 on the list. It is commonplace, and I think McKnight did well to address it. Others may disagree, of course.