> an \include-like system that allows you to
> include stuff at arbitrary positions on the page, which is what
> TUGboat actually needs.
Why do you need an \include? or in particular why do you need an
\includeonly ? Tugboat isn't so long is it?
There seem to be two issues
1) making a `master class' that can pull a series of separate articles
each from a separate file. Each of these `article files' should be a
self contained document that may be processed independantly
(although of necessity with a different class and perhaps a
slightly different look to the output when processed independantly).
2) A generalised \include/\includeonly system that does not force the
\clearpage as in the current implementation.
It seems you can have 1) without 2).
You can more or less get (1) by just having the master class redefine
\documentclass to do nothing, re-enable \usepackage for use by the
articles, and just set up whatever typographic details are needed to
handle the `front matter' of the individual articles when considered
as sections in the larger work.
There are problems when you start to consider packages used by the
different articles clashing, and issues relating to avoiding namespace
clashes with \label etc, but they are not insurmountable (probably:-).
However if you miss out one of the articles then page breaks etc will
all change. (Unless you force each article starts on a new page and
(2) is harder and perhaps not even possible in full generality,
depending on what you want to specify happens to floats, whether or
not they are allowed to float out of or into regions of the document
that are potentially not included. (One of the main reasons why the
current \include forces a \clearpage before and after the included
section is so you don't have to worry about floats crossing these