I received the New York Post Fiendish Su DoKu puzzle paperback by Wayne Gould. In the introduction he writes:
"A valuable tip from Wayne Gould: If you are writting too many pencil marks, it means you are not understanding how the puzzle works. You may be relying too much on mechanical procedures, without appreciating the underlying logic. If, in time, you can shake yourself free of written pencil marks, you will see the Su Doku puzzle for what it is - a thing of beauty!"
The puzzles in the book are not very hard and do not require any advanced techniques. I try to minimize pencil marks but I usually end up writing in some or all of the candidates. I would like to solve these types of puzzles without pencil marks, I think it would be a challange, but I don't know how. I tried searching the internet for help or techniques to do this but did not find much. Are there any examples of these types of puzzles that are solved without pencil marks where the author goes throught the logic of how each number is entered in the puzzle?