It kinda works.
I'm 6 days into NaNoWriMo and I've added 12,199 words to my manuscript. If I can keep up the pace then I think I'll have a complete first draft done by the end of the month.
It helped that for the first two days I was under the mistaken idea that I had to generate 7000 words a day. I have no idea where I came up with that number--maybe I read it on the blog of someone who knew they could only write two or three days per week and thus set themselves an insane daily word goal? I mean, I'm not that bad at math (50,000 words divided by 30 days makes 1666 words per day)! But the goof up turned out to be kind of useful since for the first couple of days I really cranked out the prose (and ate a lot of the kids' Halloween candy). I didn't make 7000 either day, but wrote about 8000 words in two days. That got me ahead of the curve so that, when the critters had the day off school on Tuesday, I had enough of a buffer to skip a day and didn't have to feel guilty about wanting to park them in front of crap videos for hours on end.
And since my initial burst, I've found that writing 1500 words per day isn't that hard. No, they aren't the best words I've ever written, but some of them are decent and others hold the germ of a good chapter. The important thing is that I'm getting the damn plot cranked out and not getting all OCD and revising the first 50 pages over and over again.
I needed something to slap me out of the pattern I'd fallen into and it looks like NaNo was just the thing.