A while back I found myself at the forefront of the sudoku craze. It quickly developed into an addiction, so I quit cold turkey. But I relapsed--solving five puzzles per day at my peak-- and had to quit again, never looking back. (Seriously. I've been clean for over two years. Not that I'm counting.)
One afternoon, I made a sudoku puzzle for my younger sister. I figured I could do it by hand. The first part seems simple at first: you have to line up the numbers just like when you're solving it, according to the rules, except you get to pick where many of them go. Once started, you realize the complications, that it's best to work in pencil, because you're likely to screw up. Worst, though, is when you realize the scheme you've plotted can't continue, because 62 boxes in, you need two 3s in the same row.
The second part is even trickier. Now, with your key in hand, you make a copy and start erasing. The goal is to clean up as many spaces as possible, so the solution logically follows from a minimal starting point. Too many numbers gone, and your puzzler might as well make their own. Too many clues, and they might as well try today's crossword.
(If you're planning on trying this for yourself, for the second part, think symmetrically along a diagonal, as if you're folding the puzzle in half to make a triangle. If you erase one number, erase another that is its diagonal doppelganger.)
All this is to extend a metaphor, and a rather poor one, for writing a novel. Even though I'm not a big fan of the Mystery genre, every novel I've ever liked has been a mystery at heart. Suspense, foreshadowing, plot twists, flashbacks, murder, tortured souls... Bulgakov, McEwan, Pears, Orwell, O'Connor, Fuentes, Dostoyevsky... It should surprise no one that one of the most influential novels in my life is The Count of Monte Cristo.
My point: every story has a certain structure, a certain logic, that seems to grow organically until the point where the words form naturally into rows, columns, and grids, like wisteria on a trellis. Unlike crafting a puzzle, though, the solution and the creation can swirl about together, reshaping each other until the story is complete.
If you're a writer, I suppose I'm not telling you anything new. It's just that I've found a new obsession. I'm 8,000 words along, hurriedly filling in rows and columns and grids. I'll let you know when I'm finished erasing.