Single Loop With Dual Content Area

Lets first start with a bit of knowledge-base:
the_content is this

/**
 * Display the post content.
 *
 * @since 0.71
 *
 * @param string $more_link_text Optional. Content for when there is more text.
 * @param bool $strip_teaser Optional. Strip teaser content before the more text. Default is false.
 */
function the_content( $more_link_text = null, $strip_teaser = false) {
    $content = get_the_content( $more_link_text, $strip_teaser );
    $content = apply_filters( 'the_content', $content );
    $content = str_replace( ']]>', ']]>', $content );
    echo $content;
}

For more information on how the content is generated check: get_the_content()

So the video and write-up will be $more_link_text values generating at a <a href="https://wordpress.stackexchange.com/questions/160788/...">$more_link_text</a>

Now back to you

If in your content you have information that you want to be filtered (divided / separated) in two areas do this:

add_filter('the_content', 'filter_only_video')
the_content();
remove_filter('the_content', 'filter_only_video');

add_filter('the_content', 'filter_only_write')
the_content();
remove_filter('the_content', 'filter_only_write');

And in functions.php add this:

function filter_only_video($content) {
    // your code that only keeps that video part on (removing the rest)
    return $content;
}

function filter_only_write($content) {
    // your code that only keeps write-up part on (removing the rest)
    return $content;
}

If you write these two functions correctly you can show what you want in two separate places.