the easy/hard writing and the many skills and things any author should have and know

Most of the people think the most important skills for any author should be the good knowledge of the language, the good writing skills, or the good imagination. But I guess any writer would say these are just some of the basic skills. The writing of any book requires much other information, many other skills that are connected to that information. For example, if a writer writes a book describing a fierce battle with swords, he or she has to be familiar with many (or all) of sword battle techniques... or even has to "take part" in such a battle, may be even more than once... That way the description of such events in the book will be really amazing (and true at the same time).
Books could be also a way to educate anyone. Any author use much information in his/her books, and in most cases that requires months or even years of research and collecting of useful information for creating new facts, thoughts and plots. Sometimes, this could be very hard, even harder than any physical work or activity, like digging of channels with a spade...
Few people realize what a great and hard work the writing of a book requires. Bernard Werber read and collected information about his “Ants” novel about a year, then used just about 18 % of the read facts. John Grisham uses his years of studying law and practice to write his bestsellers in the best possible way.
I’m sure any author could name a lot of similar examples? As for me, my hair stand on end when I remember how many books (the Bible, Quran, many books and a lot of information about octopuses, enormous quantities of facts about antiquity, etc.) I must read just about one of my future books – “The Lord Of The Christ”…
I feel almost the same, when I remember that I have to learn how to dance exactly like Michael Jackson for another book of mine – "Lake Mystery"… Or the fact that I will have to become a bodybuilder and learn all the details about bodybuilding to write my "Incredible Future"…
I’ll be glad to hear some other opinions from other writers, editors, or readers about the hard/easy writing and the hard/easy ways to create these incredible things we call books…

http://www.strategicpublishinggroup.com/title/TaleOfTheRockPieces.html, http://allanbard.hpage.com, http://allanbard.hit.bg,
http://www.youtube.com/watch?v=0yw3a5n00FI

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