And, by the way, how did you know that "Moving to the opposite corner
of a 3x3 square always takes four moves." Did you, perhaps, read this
in a book? Did you figure it out yourself? Or did someone teach you?
(someone who themselves probably read it in a book) If it was,
directly, or indirectly, received from a book, how can you maintain
that such a book is useless?

On 09 Oct 2007 11:21:14 +0100 (BST) David Richerby
wrote:

I'll admit to being utterly flabbergasted as to why somebody would
write an eighty-page book explaining how to do something this simple.

I never claimed you had to read the entire eighty-page book to learn
the methods within. In fact, in my review I explicitly said that you'd
only need to read about 8 pages of it to learn the method. The rest of
the book explains why the method works, provides examples, exercises,
answers, reference, and index... with lots of diagrams to boot. All
this makes the method easier to learn.

I, for one, am glad the author didn't try to cram the whole method in
to a single page, without any examples, explanations, exercises,
diagrams, or answers... as I would have probably had a harder time
learning it.

Anyway, no one will force you to read the entire book. You can read as
much or as little of it as you find useful.