The edit interface is quite easy to use, even for less technically savy. There are three modes available:

Edit mode 

This mode provides an overview in a tree pane and preview in another pane. This mode enables complete administration of the web site without relying on the templates. See screenshots.

Drag&drop parts

There is a mode where page parts can be dropped onto zones directly on the page. Existing parts can also be dragged around and sorted. See screenshots.

Edit on page

Content can be edited directly while navigating the site. Pages can also be created and deleted without entering edit mode. While this isn't as powerful as the edit mode it's an easy way to manage content.