Ever drop a plate and have it break exactly down the middle? There's your analogy for what happened with draft 4 of the outline for Always Outnumbered, Never Outgunned. I got to the halfway mark, and realized everything after that point had been, uh, "rendered inoperative" by all the changes I'd made.
Liberation or disaster? It's great to not have to walk around with the baggage of one's legacy decisions in a story, to be sure. It's also a mess to have to come up with something to replace it all. Guests are coming over for dinner, you've just burned the roast you were making, and there's nothing else in the fridge. Sometimes, though, you have to burn the roast to make a better meal.
Dostoevsky was notorious for doing this in a very literal way. When he found a better way to do something in a story he was working on, he would consign the original manuscript, and most of the notes, to the flames. Some of that was practical; after his time in prison, the government continued to keep tabs on him, and he didn't want anything he was working on to be misconstrued as evidence of seditious behavior. But some of it was the need to free himself entirely from the old plan, to not have its dead weight holding him back in any form.
Burning an existing manuscript outright is pretty over-the-top these days. With a computer, it's easy enough to just open a new document and shove the old one into an archive folder somewhere. (What Fyodor would have thought of these tools, I can only wonder.) But I've thrown out far more work than I've ever kept, and I regret losing none of it. There were no works of lost genius there; there were false starts, immature realizations, and notes towards better things. None of them constituted a roast I would want guests to sit down to and feast on.
Zen teaches that a good thing is a bad thing and vice versa — that what feels like comfort can be mere complacency, and that a difficulty is a way for you to level up. This seems like a bland homily until you actually get into the habit of turning over the rocks in your life to see what's underneath all of them.
It took the breaking of the plate to see that this particular plate had in fact been broken for a long time. My earlier drafts of the outline skimped, badly, on how the second half of the story was supposed to come together. All generalities, no specifics. What better way to fix that than to start from scratch?