If you over-plot your book you strangle your characters. Your characters have to have enough freedom and life to be able to surprise you.
"The Diagnosis" had ten drafts of very significant changing, where I went through the whole book, wholesale and changed everything. Then the last year or so it was making small changes. I would do something and let it sit for three months... just brood about and decide I needed to slightly change something here or there. Or one character wasn't quite right. But I think everybody goes through this.
That's the fine balance of a fiction writer...to be able to give your characters enough freedom to surprise you and yet still maintain some kind of artistic control.
Another strand of my writing is the importance of the idea. If you think about fiction writing as a spectrum, where at one end of the spectrum in the infrared, are the story tellers, and the people for whom creation of wonderful characters and telling a good story is the most important thing.
In fiction writing ideas have to be handled extremely carefully. You can't let your characters just be mouthpieces for your ideas. They have to live and breathe on their own.
