The first four chapters of the book are
sealed, and ready for printing. Spell checking, re-reading, removing overfull
\hbox (you don’t know what an overfull \hbox is? You haven’t lived! :-)
), re-reading, etc. Then there are the diagrams: move that box left a mm, un-
bold that word, align the caption, highlight the arrow. A huge amount of last-
moment changes and tweaks. Nothing serious mind you, but a lot of work
nevertheless. Four chapters down. Twenty to go. And eight appendices
(appendixes).