I remember something a long time teacher said, "Nick, if you make a suit out of a gorrilla, the arms are too long." I forgot why that was relevent to the topic of theming menu trees.
Moving on, here's a nice little function I wrote to return a themed menu tree by path.
<?php
// will return all menu items under "administration".
print theme('menu_tree_by_path','admin');
// will return links to all node submission forms
print theme('menu_tree_by_path','node/add');
// return the correct menu array by path
function menu_get_mid_by_path($path) {
// oddly, menu_get_item accepts a path, but returns the parent id.