Usually vocabulary files stay small. They should, because your model of the data should be much smaller than the data itself. Factotum is not an acronym. Factotum is an anti-database. While it provides many of the functions of a database it never takes the data away from you.
Data is always accessible and modifiable in any text editor.
No mysterious database management files to prevent you from getting at data. Factotum does not restrict the data model at all, in Factotum the data model is the vocabulary and you are encouraged to modify it as much as you wish. Factotum assists you in doing this by telling you which facts don't have a match in the vocabulary, and then you can go and fix them. Factotum is anti-database in several other ways. It does not try to provide access to the data for programs to update and search the data.