I think this is misunderstanding the purpose of the Litterae Ignotae -- it wasn't just a substitution cipher for encrypting text for security reasons, but a writing system for an artificial language called the Lingua Ignota. It's not entirely clear what the purpose of this language was, but it may have had some mystical significance to herself and her followers.<p><a href="https://en.wikipedia.org/wiki/Lingua_Ignota" rel="nofollow">https://en.wikipedia.org/wiki/Lingua_Ignota</a>