Templating Tutorial

Maybe this is already included, but someone in the English mailing list asked the following:

"obviously much thought has gone into the creation of the new Introduction package ... i was wondering if there is some documentation available that explains the different parts and concepts, why things are setup the way they are or just a general overview and insights from the people who created this ?"

I was wondering if this new tutorial followed the same structure as the Introduction Package, and thus could explain the logic. Else it could be an appendix to the Getting Started tutorial, although it's somewhat out of scope (but maybe ok as an appendix).