g1smd - 12:06 am on Jan 11, 2013 (gmt 0)

Lame rule creation could give three redirects...
example.com/cms/page.php -> example.com/page.php -> example.com/page -> www.example.com/page
before content is delivered at the right URL.

If you examine the set of rules above (21 to 25), it doesn't matter what you request:
example.com/cms/index.php
example.com/cms/index
example.com/cms/
example.com/index.php
example.com/index
example.com/
www.example.com/cms/index.php
www.example.com/cms/index
www.example.com/cms/
www.example.com/index.php
www.example.com/index
there will be a single step redirect to the canonical URL -> www.example.com/

Likewise, for any of these...
example.com/cms/page.php
example.com/cms/page
example.com/page.php
example.com/page
www.example.com/cms/page.php
www.example.com/cms/page
www.example.com/page.php
just one redirect step to get to the canonical URL -> www.example.com/page