CyberCourse is software for writing textbook-like things.
An important goal is that content lasts for years (think decades) without change. It will work on new devices as they come along. Authors can move content across platforms (CyberCourse to ELMS to Moodle to PeeWee's Buckets o' Content Management System) without needing to rework content. Well, not much anyway. What rework is needed is done once for all nodes with regex.
CyCo uses CKEditor as a semi-GUI, not its usual WYSIWYG self. Authors write in reStructuredText. Think Markdown, but standardized.
The editor hides geeky implementation details, like paths to image files. When an author inserts an image, s/he sees the image, not the path to it. This combines the precision of reStructuredText, with the usability of a GUI.
This video ...
... shows how author notes work. They look like sticky notes in a standard browser. If you have permission to see them.
Author notes are stored in plain text in the database, as reStructuredText directives. Directives are a standard way of extending the language. Standardization makes it possible to move content to another platform, and have it work in the new context.
Let me know what you think.
Kieran

Comments
Where can I find this CyberCourse Software
I was looking for it online - but could not find it...