One thing is clear: people either love this book or absolutely hate it. Illustrating this, three of Amazon.com's six reviewers (December 23 2016) give Decoding Chomsky 5 stars (the maximum) while 3 give it just 1.

In fact, the book has received mostly favorable reviews (see extracts below), but, as might have been expected, life-long Chomskyans are unremittingly hostile. If you enjoy shrill partisanship and name-calling, here are two dismissive reviews by (1) Norbert Hornstein & Nathan Robinson and (2) Robert Barksy.

This is Chomsky from a new perspective, the perspective of a social anthropologist. It connects his science with his politics in a novel and convincing way. Knight has dug deeper and made more interconnections than anyone has done before. The result is truly revelatory.
— Michael Tomasello, author of 'A Natural History of Human Thinking.'
Chris Knight has done the intellectual world a favour by exploring, with a critical and comprehending eye, the twists and turns of the thought of Noam Chomsky. Anyone who wants to understand the political and intellectual development of ideas that have dramatically altered modern science and political activism should read this book.
— Daniel L. Everett, author of 'Language: The Cultural Tool.'
Few disagree that language has been a game-changer for the human species. But just how we came by language remains hotly contested. In ‘Decoding Chomsky’, Chris Knight strides into this minefield to bravely replace miraculous leaps and teleology with a proposal that actually makes evolutionary sense.
— Sarah Hrdy, author of 'Mothers and Others: The Evolutionary Origins of Mutual Understanding.'
This is one of the most exciting scholarly books I have read in years. Decoding Chomsky will be required reading for anyone at all interested in the history of intellectual and political thought since the 1950s.
— David Golumbia, author of 'The Cultural Logic of Computation.'
A totally engrossing roller coaster ride. Riveting and revealing, ‘Decoding Chomsky’ gives badly needed perspective to an American icon.
— David Wineberg, Amazon.com
An authoritative, deeply thoughtful and very well written analysis, shedding light on a hitherto incomprehensible tangle. Knight’s revelatory investigation helps me understand why for so many decades I could never make sense of Chomsky’s various pronouncements about the evolution of language.
— ‘Fifth Generation Texan’, Amazon.com
Social anthropologist Chris Knight has, almost miraculously, solved the Chomsky Problem. I’ve been trying to solve it for 20 years; I now feel the euphoria that one of us has solved it. ‘Decoding Chomsky’ is an astonishingly well-written and researched volume that will probably be the most important work in the history of ideas, post World War II, that you’ll read for quite some time. It’s so lucid and well-researched and intellectually and emotionally gripping I couldn’t find a fault with it, though I tried.
— Michael Johnson, 'Overweening Generalist'
Really important books do not come along very often. But here is one of them.
— Jack Conrad, 'Weekly Worker.'
‘Decoding Chomsky’ will make uncomfortable reading for some because while Knight celebrates Chomsky’s anti-racist and anti-imperialist politics, he reminds us of the other Chomsky, the world-famous linguist. Most of us in the labour movement know little and care less about this side of Chomsky’s work. Why should we? It’s highly technical, appears irrelevant to our activism and anyway, who am I to judge? Chris Knight thinks we should care.
— Jackie Walker, 'Labour Briefing.'
Knight offers a sustained argument against the view that Chomsky’s work as a linguistic scientist can be separated (compartmentalised) from the military and state ties of the institution in which he worked, the Massachusetts Institute of Technology.
— Andrew Coates, 'Tendance Coatesy.'
Knight argues that Chomsky needed to deny any connection between his science and his politics in order to practise both while based at the Massachusetts Institute of Technology, an institution that was heavily funded by the US military… Trenchant and compelling…
— Marek Kohn, 'New Scientist.'
I enjoyed reading this book... If you’ve ever pondered the way Chomsky acts like he’s basically two separate people, you will find this book well-stocked with quotes and anecdotes that outline the strange relationship between Chomsky and Chomsky…
— Lauren Gawne, 'Superlinguo.'
Knight says his ‘subversive intention’ is ‘to serve justice on Chomsky the scientist without doing an injustice to Chomsky the conscience of America.’ Now why should that be subversive? Any voice critical of Chomsky risks being dismissed as yet another right-wing defender of political orthodoxy, but given even the most superficial examination of Knight’s biography one could hardly question that he supports the substance of Chomsky’s views (as do I).

Nonetheless, he shows how Chomsky has acquiesced in – more than that, has participated in and abetted – a radical post-war transformation of the relation of science to society, legitimating one of the significant political achievements of the right, the pretense that science is apolitical.
— Bruce Nevin, 'The Brooklyn Rail.'
‘Decoding Chomsky: Science and Revolutionary Politics’, by Chris Knight, was a decade in the making and may be the most in-depth meditation on ‘the Chomsky problem’ ever published… You don’t have to entirely buy Knight’s solution to find his book a compelling read… He accuses Chomsky of creating a modern linguistics mired in ‘tunnels of theoretical complexity, impenetrability and corresponding exasperation and interpersonal rancor without parallel in any other scientific field.’ He dismisses Chomsky’s core ideas as nonsensical and makes the case that developments in evolutionary psychology and computational linguistics have long since left his theorizing in the dust… While Knight’s disdain for Chomsky the scientist is impossible to miss, so is his admiration for Chomsky the activist. He writes that ‘it would be difficult to think of any prominent academic who has done more to take to the streets, risk arrest, measure up to the events of the day, speak truth to power and, in the process, endured ferocious political hostility matched only by passionate grass-roots support.’
— Tom Bartlett, 'The Chronicle of Higher Education.'