Well, yesterday I did minor revisions on 10 chapters, so far today I've done another 5. Right now I'm just doing small, easily fixed things and making a list of the bigger stuff. Maybe I'll end up cutting some of what I'm fixing now when I do the larger changes, but with the grammar and awkward sentences out of the way, I'll be able to focus on the big picture. It also gives me time to go over the whole thing, some of which I haven't touched for 8 months.
It's funny the things I'm learning as I go through the comments on these chapters. I can now recognize a comma splice, there is one particular aspect of dialogue grammar that I either forgot or never understood, and I can repeat phrases or words in close proximity and never notice, no matter how many times I read through the passage. Thank heaven for smart critique partners, who know about these things and patiently mark up the same problems over and over. Other small things are fun to correct. Seeding the text with foreshadowing is pretty fun - it is hard to foreshadow properly if you are trying to foreshadow something you haven't written. Also, when you are discovery writing, you tend to 'discover' things about the world or culture that you should have introduced long ago. It isn't too difficult to go back in and scatter those elements back through earlier chapters or bring stuff I forgot back to the middle and end. My list of big things is growing as well. Some of them became clear about 3 months ago, but I needed to get the thing written before I corrected them. I had a character arc in mind for one of my guys that completely flopped, and I need to go back in and change him significantly. I love to retain mystery, but you can't do that with everything - I have to be above-board with the less important things so the things I chose to keep mysterious really pack a wallop when I reveal them. And I need to add about 3 chapters in the middle, where I didn't spend enough time. Plus, I want to do something slightly different with the ending. All and all, I'm making progress. It's going faster than I expected.