Before I start, I should make it known that I find Oz Clarke a very engaging and entertaining character with whom to run through the minefield of oenology. His TV show with James May was utterly fantastic, his frustrations at May's philistine nature showing through time-and-time again. On paper, however, his personality isn't so infectious and it instead left a rather lip-smacking, tannin-rich after taste having read this book.
I am an absolute novice when it comes to all things grape. That's why I plumped for this book - with many of the recommendations pitching it at just my level - and parts of it are certainly very useful in developing one's knowledge of wine. However it did at times feel as though you were being led on Oz's wine tour in which he goes into detail about the wines to which he is partial and always providing subjective insights into the wines, regions and grapes. There are useful guides, yes, but there is also a lot of wit and diatribe which, for me, took away from the guidebook essence of this volume.
I wouldn't urge anyway to shy away from this book as it is an accessible start-up but I would almost certainly recommend you supplement it with a more hardy and objective tome like the Oxford Companion to Wine if you are truly to become the cultured student of oenology.