I have a longish review of Andro Linklater's "Owning the Earth" at the Library of Law and Liberty. Linklater's project was to offer a story of the development of land ownership in Western societies. Not the smallest of endeavours in itself. Land ownership is not an easy subject and requires extensive historical knowledge to be mastered. On top of that, Linklater plays with the history of political thought and, still not satisfied, finishes his book with a (rather unconvincing) chapter on the financial crisis.
Now, why do writers do this kind of thing? How come when you are writing a book you become willing to put down whatever thought you have in your mind, regardless of the subject you picked for yourself?
I suspect that, whenever we are playing with words, we'd do the world a better service if we cut all but 15% of what we have written ourselves. People tend to drag on when they're speaking and when they're writing. Excessive length makes an argument less focused, more repetitive, and ultimately less persuasive. All authors will tell you that: "cut unnecessary words!" And yet very few of us wordsmiths are capable of doing it with our own prose.