protected function _initProduct($block = null)
 {
     static $product = null;
     if ($block === false) {
         $product = null;
         return;
     }
     if (!$product) {
         $r = parent::_initProduct();
         if ($block === true) {
             $product = $r;
         }
         return $r;
     } else {
         return $product;
     }
 }