You're welcome Marcio, glad I got there in the end with my explanation!
Re the User Guide, in the section on Configuration Profiles: https://www.nvaccess.org/files/nvda/documentation/userGuide.html#ConfigurationProfiles
It does say: "A configuration profile contains only those settings which are changed while the profile is being edited. "
But I appreciate that sentence is more obvious and makes more sense once you already know what it means and is easy to skip over initially (especially as
only a couple of lines into that section.