I think that "putting it away and letting it lie fallow for a month before beginning the edit" is one of the absolutely BEST things you can do to a novel. For various reasons, there was a delay of about 18 months between the time my second novel was published in the UK and before it came out in the US. About a year after I'd handed it in, I re-edited the book, with the result that the US edition is MUCH stronger than the UK. To the point I feel a little embarrassed by the first book. 