'Why is it necessary to write a 400 page book, explaining that God is a delusion, if this is not self-evident?

No its not - he was just making money off people that have nothing in their lives. Our Vicar did this talk about that very book. Here is the link if you are interested http://www.htb.org.uk/audio/has-science-disproved-...

You need to read the books on self-denial and delusion to understand the human proclivity to believe in things that are not real so long as it aids one's survival.

The short answer is a book to demonstrate a particular delusion would be fairly thick if the delusion occurred because the people who believed in it did so because they didn't really understand the failure of proof to their delusion.

If it were really "self-evident" that no God exists, no sane person would believe in him. So either he really does exist, or there are billions of insane humans running around on this planet. It probably takes at least 400 pages to try to mount a good argument for the latter, and maybe ten times that many to come up with a really convincing one.

Because apparently some sheeple are not able to think or function without reading ideas and or/instructions on how to live from a book. Popular activity with all religions and requires much blind faith.

Richard Dawkins feels the need to reafirm his Atheist beliefs.

That books is an excellent piece of literature, mostly its aimed more at Atheists, the religious believe nonsense because they are indoctrinated and choose to see what they want, this book shows the bad aspects of their delusion.

Christians have this idea that atheists are all into Dawkins. Personally I haven't even read his stuff

I guess he wanted to convince christians that they're believing crazy ****

What?

When someone has a delusion, that means they can't see something thats self-evident. It needs to be pointed out to them.

Schizophrenics for example (although thats mental illness, rather than willfull delusion)

Your question made no sense.

because a certain individual [not naming names] decided that he could sell lots of books by using his rather poor (for a biologist anyway) understanding of evolution to try to discredit religion, and throwing in a bunch of arguments that have been refuted many times in the first 500 years they were around. It worked because Americans love controversy and sensationalism.

Apparently, most people missed that one.