Nanowrimo of sorts. You?

So, it's Nanowrimo, I'm told. Yes, in November, some people grow moustaches and others (but sometimes, I suppose, the same) write novels. The idea behind the National Novel Writing Month is a simple one. All you need to do is write 50,000 words worth of novel. Don't edit, don't over think, perhaps don't even plot, just write and see where that gets you 30 days later.
I've never done it as I'm usually exceedingly busy being a lazy moo, but it just so happens that I am actually writing a novel right now. It'll never be (I hope!) 50,000 words long and I'm not writing it from scratch but it will have to do.
I hadn't realised I was writing a new book. I thought I was just tweaking the beginning of an existing opus in order to show it quickly to my publishers. I needed a new and improved first chapter and it wasn't really happening. When I thought I had more or less nailed something decent, I typed it at the beginning of my story.
And then I cheated.
First, I googled something like "the best opening lines in children's books".
Then I stole one: "I am writing this sitting in the kitchen sink" (goodies for the first person to remember where that came from) and changed the location. And that very simple trick opened such a floodgate of words and images that all I could do to avoid drowning was open a new Word document.
Now, 1,500 words later I find myself writing a story that is both new and old. The characters, the plot drive, the names are the same as in the previous version. But I'm forbidding myself to look at Take 1, to nick puns from it, snippets of dialogues or entire scenes. I'm trying to work my way through the main events of the original narrative as I remember them, while integrating the new and crazy stuff I've already come up with.
I had heard of writers who finished their first draft, stuck it in a drawer and started over again without a backward glance. I wasn't sure I could see the point. I wasn't sure I could take so much effort.
Well, look at me now!