I have an interest in languages, and thought that this would be a very interesting book to read. Unfortunately, the book tends to wander, there is no real structure to the lay out of the book, there is no clear beginning, middle and end. There are several instances where he lists off words just like that, so called loan words in English, and I am not afraid to say I never use them even though it is claimed that these are in everyday use. Occasionally there are glimpses of interesting passages but these are interrupted by more word lists.
I would not even called the book academic, even though there are lots of references. It is not at all comprehensive, as he is very biased, he mentions English in the USA and Canada, but fails to cite the influence of Irish (Gaelic) on English, and there are several examples, eg clann, he even gets the word "Uisce Beatha" completely wrong (from which whiskey/whisky come from). What about smithereens, smashing, galore, esker etc etc etc? What about Hiberno English?
Finally may I say that this book is hard going.... I forced myself to read it right to the end just to see if any references were made to Irish Gaelic.