Subdirectory architecture and SEO

I've read that burying your pages deep into the subdirectory structure of your site can negatively effect your pages from a SEO perspective.

Is there really an advantage to naming your pages:

"www.mydomain.com/directory_subdirectory_page1.html"

as opposed to :

"www.mydomain.com/directory/subdirectory/page1.html" ?

Any feedback will be appreciated.

Mario
http://www.theinternetdigest.net
Internet Marketing Tips for Small Business

There is an advantage when you name your files more like this

mydomain.com/directory/topic/index.htm

an index page is like a starting point for a whole new directory...