Non-local page-break oddities

[Joel C. Salomon]

I’m getting close to finished with my first Lilypond project, a book of some 30 scores.  I tried building the `\book` section piecemeal, including a handful of scores and tweaking the page breaks, and then another batch, and so on.

\book {
  \scoreI
  \pageBreak
  \scoreII
  \pageBreak
  \scoreIII
  \pageBreak
  \scoreIV
  \scoreV
  \pageBreak
  …
  \pageBreak
  \scoreXXXI
  \scoreXXXII
  \pageBreak
  \scoreXXXIII
  \paper { min-systems-per-page = 2 }
  \scoreXXXIV
}

The weird thing is, if I comment out all a few `\scoreX` statements, the page breaks fall where I want them.  But when I compile the whole book at once, some scores start to stretch across multiple pages in ugly ways.

I have tried tweaking with lines like

\paper { max-systems-per-page = 8 min-systems-per-page = 5 }

in strategic places, but that still fails when I add enough scores.

(It looks like perhaps using `\bookpart` around chunks of the book might help, but that re-prints the book header when I don’t want it to, and I’m not seeing how to suppress that.)

It’s hard to give a minimal example without publishing my whole project in public.

—Joel