Surprising to see that. My copy only just arrived and I have been quite impressed so far. I have a passing familiarity with the variation, but a fair bit was new to me here.
One problem may be that the reviewer is a quite weak non-player. Had never heard of him so looked it up:
http://ratings.fide.com/card.phtml?event=4637755 Only 4 rated games in the last 9 years (at least) and a rating of only 2163. I would thus be sceptical of his ability to actually be able to review effectively.
Odd criticism: a game from 1972, ECO, and a one-mover from Rybka/Junior.
As noted many times in many places, weak players can write books with PCs, but they struggle to judge resulting positions.
Similar with reviewing. Simply - he isn't experienced enough to be able to judge.
That said, I am sure Simon Williams will pop by to reply at some point to the specific criticism, when he has finished the more important matter of the British Championship.
Reviewers - if you are grumpy, having a bad day at work, wait till tomorrow.
I recommend the book - lively stuff, engagingly written with plenty of explanation by an expert in the line.