I made this change on my own board, since all moderators manage all forums, and the redundancy was getting on my nerves.
Starting at line 115 in index.php, replace
if ($cur_forum['moderators'] != '')
{
$mods_array = unserialize($cur_forum['moderators']);
$moderators = array();
while (list($mod_username, $mod_id) = @each($mods_array))
$moderators[] = '<a href="profile.php?id='.$mod_id.'">'.pun_htmlspecialchars($mod_username).'</a>';
$moderators = "\t\t\t\t\t\t\t\t".'<p><em>('.$lang_common['Moderated by'].'</em> '.implode(', ', $moderators).')</p>'."\n";
}
with
if ($cur_forum['moderators'] != '')
{
$moderators = "\t\t\t\t\t\t\t\t".'<p><a href="userlist.php?show_group=2&sort_by=username&sort_dir=ASC&search=Submit">View moderators</a></p>'."\n";
}
Being a dirty hack, it assumes that your moderator group is group 2 and it doesn't reference a lang file, but it should work.