I'm thinking about doing this. I've figure I need a good outline, so I'm made a rough of a 25 chapter book. So if each chapter is at least 2k and I write a chapter a day then I've got it easy. Course some chapters look like they may be longer. Right now I'm planning on going back over the outline, fixing errors, filling in setting details, fleshing out character details, and outlining individual chapters. I'm accepting that this "novel" is going to include a lot of fluff and probably a lot of bad writing. I'm not worrying about how generic my plot-line is. My time is limited, so I can't waste time wondering what to write. I'm also hoping to get up earlier each morning so I can write before my creativity gets used up by my job. It takes me about 2 hours to write 2k words, so I'll probably have to have a make-up session later in the day.
So it a lot of pre-writing before I even begin writing, but from my work experiences over this last year, great results don't just happen spontaneously.
So is anyone else obsessivley planning for this?