Understand that I have not bought it yet, I'm trying to clear up those questions. I am pretty capable at Dreamweaver and using extensions, but not experienced at all with CSS, I only have Joomla experience to compare this to.
Doug -- Site Sculptor is not a full-blown CMS system like Joomla. It permits a user to easily edit content on existing pages -- that said, it does not permit the wide range of site content creation provided by Joomla.
Think of SS as an initial site styling/page/navigation creator that provides pages capable of having their content updated.
You as the Site developer can easily create new pages using the template created by SS. A "user" cannot, unless they also have access to DW and the page template file.
If it's just content I see no reason why not.
In a word, no.
Hope this helps. . .