I also was confused about the scope they are going for with this. My initial assumption was that since it's GitHub, it's probably mostly for coding lessons. I read your comment though which implied it could be used for more generic lessons and I mistakenly assumed you had used the offering and had more info about it than me.

> Github/Gerrit workflows seem ideal for these types of collaborative projects

Are you suggesting complicated version control could be useful for e.g. some group of teens doing a 6 paragraph research paper in their social studies class? Again, that is just...so bizarre. That has an even lower chance of being easy for teachers or students to use than markdown.

> conclusion from your feedback is that a Google Docs-like WebUI is a requirement and my question switches to when is it appropriate to peak under the covers and see the plumbing.

That's totally valid. The difference between manually editing markdown and using a GUI toolbar is all that it takes for me to approve of the idea really. If there's a way to make the underlying format be markdown and still maintain the broad appeal of Docs/Word then I think that sounds great!