I'm currently reading one of the author's other books, Remembering the Kanji, and that book really is pretty much perfect. By contrast, this book has two major flaws despite otherwise being a great book; one, the author seems much more suited to creating interesting ways to remember kanji elements than he does to creating ways of remembering the kana. Two, many of the pronunciation guides are given based on American English pronunciation rather than British English.
For example, generally "ta" is generally pronounced similar to "TAp" or "TAtty" but in this book the author suggests using "TOp" as the pronunciation. Naturally, the author being American, all "a" sounds are given the sound of a British short "o" (as in "Orange") and all "o" sounds are given the sound of a rounded "o" (as in "Only"). There are other misleading US pronunciations given too. This leads to one saying words like "kun" - correctly pronounced so it rhymes with "pun" - in a very over-pronounced American way that rhymes with "loon".
In short, think of how Americans pronounce "Cecil" as "See-sill" and you'll see how you'll sound mispronouncing the Japanese syllabaries and consequently full words. You would normally only pronounce Japanese in such an over-pronounced way if you were shouting something, as you may shout to a friend on the other side of a road, or if you were singing.
As for the first given flaw, the author's slightly oddball method of teaching kanji meanings, attributing interesting connotations and keywords to the smaller elements and then building up from said smaller elements to the complex kanji, is employed roughly here to try and enable the reader to remember kana pronunciation and form. It's slightly flawed here for the main reason that he has to attribute some incredibly odd meanings to the elements which in my opinion make it harder to remember than merely copying out the kana a few times (a practice he's strongly against). For example, he suggests that one should remember a certain kana character by seeing it as a puppy with its tail stuck in a hole in a boomerang, hovering overhead as people below throw eggs at it. Furthermore the US pronunciation rears its head here because the element of the wacky image that's meant to aid with pronunciation is the "YOlk" of the egg - yes, you apparently say it as "yo"; however this is for the kana "ya".
Now this has all been very negative so far and yet I've awarded it 4/5. The reason being that it's a truly helpful book if you're willing to do the following: (a) find another source for pronunciation, there are many such sources on the internet and many "Learn Japanese" books and CDs compiled by British and Japanese authors and (b) are willing to sometimes ignore his bizarre stories and make your own. For example, he suggests the hiragana "ma" be remembered by the keyword "mama", with the image of a mother standing in an open field throwing large heavy swords so that they come back to her like boomerangs. All that despite the fact that "ma" looks just like a "MAst" on a boat; a much easier way of remembering it.