The writing is mostly clear on otherwise difficult topics; various catchphrases of the field are duly mentioned; references for further reading are given (both in the text, pointing to the original texts under discussion; and in the Further Reading section, pointing to summary and introductory compendia).
Otherwise, who is the target audience for this booklet? The OUP site says, in general: 'Whatever your area of study, whatever the topic that fascinates you, the series is an indispensable and accessible guide that will enrich your understanding.' Fascination of an average university-educated adult will not be enough for this particular Very Short Intro. A beginning student of philosophy might benefit from seeing some names and having their fascination stoked, but otherwise it's too fast to teach anything, even an overview unless you're already familiar with sufficiently many terms. A specialist in French Philosophy wouldn't have any use for it.
My best guess is this: the reader will most benefit (in a traditional sense of getting an overview) if they're well-versed in parsing general philosophy, curious about the development of French ideas from Montaigne onwards, and forgiving about summarising jumps, cursory overviews, and expository gaps. That's a pretty narrow audience and not an audience I was expecting A Very Short Intro would be targeting (but then I wasn't expecting much). Personally, I was pleasantly surprised to get the level of exposition that I did!
It can be a quick, helpful read if picked up at the right moment.