protected static function isHtmlResponse () {
		$app = static::$app ?: (static::$app = & \MvcCore\Application::GetInstance());
		$request = & $app->GetRequest();
		if ($request->IsInternalRequest()) return FALSE;
		$response = & $app->GetResponse();
		return $response->HasHeader('Content-Type') && $response->IsHtmlOutput();
	}