In reply to Joan Margau.

I totally agree with you. The core problem is that many users need to understand where within Wordpress they affect the look of their site. I've had frustrated users that had a theme which front-page was completely composed of widgets and they had no idea where to start editing.
Same goes for attachment driven galleries - rearranging was impossible without a plugin. Even the simple difference between a post an a page can be a mistery to some.

However I think a proper usbility-test can not just be skipped if you have anonymous user data. There is still now way to tell, what the users intention was when he was using wordpress.