I agree with you, except that good software conforms to the user's expectations, instead of forcing the user to conform to its limitations. If your application

I agree with you, except that good software conforms to the user's expectations, instead of forcing the user to conform to its limitations. If your application lets users restrict access to documents, it needs to restrict access to all parts of that document uniformly, regardless of how those parts are stored (embedded in the same file or spread out in multiple files).