It's possible to make lilypond-book translate comments and variable
names, and still have one lily-* snippet, through a gettext mechanism.
I estimate it'd take me 2 hours for implementing and testing this
properly. lilypond-book would try to translate all variable names and
comments in snippets for verbatim output, and translators would simply
have to translate the desired strings in Documentation/po/LANG.po. It
would require no more work for doc editors. The only thing I worry
about here is how to add this mechanism without bloating up lp-book with
code that would only be useful for building Lily docs -- maybe it's time
to modularize lp-book, so we can add/replace modules (and ) for such
specific features? Modularizing lp-book is not included in the 2
hours, the time I'd need for doing it is pretty undefined, but I might
raise this later on this list to ask for advice...