the client would not need to add any developer notes, the pages would already be set up by you.
you would initially configure the site to use the template.
the tutorial also shows how to set up a page that automatically lists any new pages that are created from the template.
you as the developer would set this all up ahead of time for the client.
once set up, the client would only need to create the new page form the template and populate the details, it would atomically be created for them from there.