My reading of the Therion Book suggests to me;
- that 'source' specifies the files that Therion should read and
process before deciding what to export. The source files should contain or
reference surveys and or a surface.
- that 'select' chooses which survey(s) and or
Your suggested solution, is what I do, for 3d, and it works, but I have
not used lists yet. However, it would be nice to be able to select a map
and only get a centreline with this would be good, but I suspect too
much work for it to be worth while. (plus lots of decisions about what
exactly
