Output the_title() inside the_content()

You could achieve that with a filter on the_content:

function my_the_content_filter( $content ) {
    global $post;
    if( 'testimonial' == $post->post_type )
        $content .= ' <em>' . $post->post_title . '</em>';
    return $content;
}
add_filter( 'the_content', 'my_the_content_filter', 0 );