Defining website scope using Sitemap protocol

Dear all, 

It seems that a good number of website owners / webmasters submit a sitemap to search engines.  The schema of choice for this sitemap (file) is apparently the Sitemap protocol - http://www.sitemaps.org/ (supported by Google, Yahoo!, and Microsoft.)

What would your thoughts be on using this sitemap file generated for a website, by the website owners / webmaster, to define the scope of a website? Possibly answering the question - How can an evaluator express the scope of a website.

Would be interested to hear thoughts / comments.

All the best 

Alistair