Originally Posted by gmw
This is a long-winded way of opening a discussion about how much reworking of your manuscripts you tend to do, and whether you think there is such a thing as overworking the manuscript - and, if so, how do you tell when you have reached that point?
Anything can be overdone. Would you like to spend the rest of your life working on one novel? There are too many examples of perfectionists who continue to whittle a perfectly fine piece until they have nothing but sawdust.
You have several options:
Work on it until you're reasonably happy with it.
Work on it until you're sick of it.
Work on it until you decide that you should scrap it.
Find someone you can trust to make the decision for you.