Avoid duplicate content in DC.title

1. As mentioned in DC.Title.inc at line 11 at the moment only nodes can get an automatic DC.title tag:

// http://drupal.org/node/103399 : we are unable to drupal_get_title(),
// so unfortunately, only node-pages can get a DC.title.

But nonetheless for all pages that are not nodes in line 33 the DC.title is filled with the site name and the site slogan. That means that a lot of pages (all which are not nodes) get an identical DC.title tag. I wonder whether this could be rated as duplicate content by search engines.

So I propose to delete this lines:

    else {
      $value = variable_get('site_name', 'Drupal');
      if (variable_get('site_slogan', '')) {
        $value .= ' | '. variable_get('site_slogan', '');
      }
    }

2. In all other cases the DC.title is filled with the content of the html tag. It seems that this could also be seen as some sort of duplicate content. In http://www.vala.org.au/vala2000/2000pdf/Sokvitne.PDF I found:

The DC.title field will be checked to see if it simply duplicates the HTML element tag . There may be a potential loss of retrieval capacity if DC.title merely replicates a retrieval point that already exists.

So I wonder whether the DC.title should be switched on, if there are no manually edited DC.titles.

From http://drupal.org/node/276838 I am afraid, that turning on DC.title will cause a ranking problem.

It would be nice to hear about other experiences.