public function is_quickgrading_modified($userid, $grade) {
        $commenttext = '';
        if ($grade) {
            $feedbackcomments = $this->get_feedback_comments($grade->id);
            if ($feedbackcomments) {
                $commenttext = $feedbackcomments->commenttext;
            }
        }
        // Note that this handles the difference between empty and not in the quickgrading
        // form at all (hidden column).
        $newvalue = optional_param('quickgrade_comments_' . $userid, false, PARAM_RAW);
        return ($newvalue !== false) && ($newvalue != $commenttext);
    }