I’ve never used this feature, but here’s how I’ve considered using it. So this is untested by me, but should be a starting point and I think it would answer your question.
Say you have a series of stories from the Prophets, and you’ve created individual modules and published them as pamphlets over time. So you have a series of files in your Modules directory like:
adam.sfm
abraham.sfm
david.sfm
isaiah.sfm
etc
Now you want to create a book called “Lives of the Prophets”. Rather than create a new module where you copy and paste the contents of those independent files into the new module (and then have to keep two locations up-to-date in the future), you can simply create a new module which says
\mod adam.sfm
\mod abraham.sfm
\mod david.sfm
\mod isaiah.sfm
It would then create a book with each story one after another. You might add in some extra markers to create title pages or page breaks, but most of the work is already done by the original modules.
