protected function _loadLayoutXml() {
        Varien_Profiler::start('turpentine::helper::esi::_loadLayoutXml');
        $design = Mage::getDesign();
        $layoutXml = Mage::getSingleton('core/layout')
            ->getUpdate()
            ->getFileLayoutUpdatesXml(
                $design->getArea(),
                $design->getPackageName(),
                $design->getTheme('layout'),
                Mage::app()->getStore()->getId() );
        Varien_Profiler::stop('turpentine::helper::esi::_loadLayoutXml');
        return $layoutXml;
    }