Hi Kev
Thanks for the question. TW5 is designed to support publishing to the web as a classic "fat" TiddlyWiki HTML file, as a skinny TiddlyWiki HTML file (where the tiddler bodies are retrieved on demand from separate files in the same directory), or it can generate static HTML files which can be viewed without JavaScript if necessary.
The intention is to be able to use those options together - for example, storing a TW as a fat HTML file but to store alongside each tiddler as a static HTML file.
Best wishes,
Jeremy