Dave - sounds like the re-editing is working for you. I'm so pleased.
I've found in the past that I've suddenly opened the wrong document and am editing an older version of a WIP, and only realize after I've done some significant work on it. When I then compare the two documents, they may be a little different, but both are good in different ways. Sometimes editing for a second time produces a better edit.
I tend to have 157 versions of each ms saved, and occasionally can't remember which was the latest and greatest. It's all a process, so no writing is wasted.
Thank goodness for cut & paste, and save as. These things are the writer's friends.
OMG. I did that once and I nearly cried because I couldn't remember what those changes were. So logically I didn't want to overwrite. Needless to say that I just had to do the editing all over again. *sigh*
I tend to keep one word file per draft. So I have four in total. My 5th will come after betas (the suspense is killing me). I'm anticipating it being ripped apart, and for some strange reason, I welcome it. Is it masochistic to want people to tell you it's terrible? My reasoning behind it is 1) I think my ms is complete trash 2) There's only room for improvement.
There's nothing more satisfying to me than seeing comments on my work - be it positive or negative - because it allows me to see what I cannot see because I'm too close to my work. Logically I'm devastated at first, but after I give it a bit of time and thought, I feel like my writing is better for it.