I have to disagree Ed. Your wrong. That's not the kill cord, its a cord from his flotation suit. Its on the starboard side, whereas the kill cord is under the ignition on the 703 box, port side mounted on this boat.
You may have a point by default, as its not clear that its being used when under power. Later in the video it looks like its connected to the key (in other words useless) but the boats at rest whilst they are near the stern. Its not conclusive that they do not use it under power so maybe they do ?
Peter @ Boatsandoutboards4sale