I'm actually finding it hard because I feel like I need to re-write all the old chapters each time I write a new one. The problem is as I go from A to B to C w

I'm actually finding it hard because I feel like I need to re-write all the old chapters each time I write a new one. The problem is as I go from A to B to C when I get to D I realize I really want the code to be in a different shape. But to do that I either need to make a C' where I take a timeout to explain why I'm refactoring the code before I move on to D. Or, I need to go re-write A, B, and C so they fit directly into D. Making C` sucks because it's irrelevant to whatever the topic is. But re-writing is also a ton of work. You could argue I should start at Z and work backward but I'm writing as I go so I don't know what Z is yet.