I haven't looked at this plugin in any detail, but it seems to me that this Calibre FAQ applies:
Why doesn’t calibre let me store books in my own folder structure?
Changing anything in the library directly is considered a Bad Idea in general.
And I don't think this will necessarily work. My (admittedly vague) recollection is that if you give windows a path name in all lowercase or all uppercase, it assumes it is caseless. IE, it only saves case when both upper and lower are present, which isn't always true.
That said, it's your computer, do what you want.
I would not recommend making this available for everyone, but linking to the github for those savvy enough to understand and use it seems about right to me.