Looking at Cameron through the wrong lens
The second was that, having sailed through life on very much an even keel, Cameron was massively affected by Ivan, and all the heartbreak, misery and complications that a desperately handicapped child bring to a family. Insofar as Cameron has any great personal complexities, I suspect that this is where you ought to look for them - not in his schooling or upbringing.
But then, most people aren't tormented by internal demons, or driven by insecurities and anger. When you've said that Cameron is a charming, upper-middle class chap with a solidly county background, you've pretty much covered all of his internal life that needs to be covered.
I'm not sure, therefore, that the criticisms of Cameron brought by Jason Cowley of the New Statesman in his review of the book are all that useful - or even that valid. There is a lot of chipping at Cameron's intellectual capabilities. The view that Cameron's parents' household was "not a bookish one" is, for example, interpreted as meaning that there was a paucity of books there - something rather different. Equally, Cowley states (as of fact) that Obama is Cameron's clear "intellectual superior", which is a touch tendentious. The best evidence we have as to Cameron's sheer intellectual abilities comes from his old tutot, Vernon Bogdanor, who has described him as "an outstanding undergraduate", and "one of the ablest" that he taught. I think you need a touch more than an unreliable memoir, and a rather turgid book of political thought to demonstrate clear intellectual superiority.
What's strange about the review is that they take what is probably Cameron's most attractive feature as a politician - his preference of a general outlook and belief system to a more rigid ideological dogma - and try to turn it into a negative. Although, I suppose that's pretty much what you'd expect from the New Statesman.