twenty eleven child functions addendum for sidebar page

add_filter('body_class', 'adjust_body_class', 20, 2);
function adjust_body_class($wp_classes, $extra_classes) {

if( is_page_template('sidebar-preinsulated.php') ) :
// Filter the body classes

      foreach($wp_classes as $key => $value) {
      if ($value == 'singular') unset($wp_classes[$key]);
      }

endif;
// Add the extra classes back untouched
return array_merge($wp_classes, (array) $extra_classes );
}