This book is really two books in one. It offers strong advice on personal investing, and it is a damning critique of the financial services industry.
Swensen has an outstanding record as chief investment officer for the Yale endowment, which has shown strong returns from sophisticated investments. However, Swensen strongly advises that private investors take a very different approach, concentrating on core asset classes and using low cost passive funds. It's a convincing case, but one which is put much better in Tim Hale's book "Smarter Investing".
Swensen puts strong emphasis on alignment of interests between investors and those who sell or manage investments. It's an important point, and one that does apply to private investors as well as to sophisticated institutional investors.
The second half of the book is really a damning critique of the financial services industry. It's an eye-opener for the private investor. The abuses are pervasive and deeply embedded, and Swensen clearly believes that the financial services industry will always have the upper hand when it comes to exploiting private investors. Whilst the book focuses on the US, and the abuses might be different in the UK, it seems naive to think that the UK is really substantially better.
Overall this is not an easy read, though Swensen's mounting derision of the financial services industry does become amusing towards the end.
If you're after a guide to investing read Tim Hale's book instead - it's covers the same investment principles, and much more besides, in a much more readable style. If you know the basics and you want to go into investing with your eyes open to the exploitation you will face, read this.