How to not treat categories as tags in feeds

Tricky. It lumps categories and tags together pretty good. Had couple of approaches here is least messy:

add_filter('the_category_rss', 'remove_rss_categories');

function remove_rss_categories( $the_list ) {

    $categories = get_the_category();

    foreach ($categories as $category)
        $the_list = str_replace("<category><![CDATA[{$category->name}]]></category>", '', $the_list);

    return $the_list;
}