This morning, I made it through the end of my last example and got the whole next sub-section written. Fortunately, for the most recent subsection, I was able to refer back to the previous examples, so I did not need to go through that arduous process again!
Now that I’m back into explaining the process, and don’t need to look up the details for each paragraph, my writing pace is climbing back to an acceptable rate. I still have a lot of book in front of my to write – I’m just over 40% of the way to my word count target, and about that far into the content, as well – but at least it no longer feels like it’s going to take forever to write. There might just be hope to get it out by April, after all!