Well, it does help significantly, but not necessary. Jack moved his head out of the way first, and had a lot of head movement. Many good golfers move their head during the swing. Everyone is different. We all would love to be like Fred Couples and be doubled jointed at the neck. But for the rest of us, the secret is: Keeping your eyes still and on the ball from the beginning of the swing, impact and for as long as you can hold them their after you make impact. This keeps the head still for as long as possibly can be done by each individual.
Work on a drill making half swings back and through, keeping your eyes on the ball each time. Try with your feet together too. You will notice how many times your eyes want to dart away. “Golf ADD” I call it. This will provide you with better ball contact and better misses. Call me if you have any questions and happy hitting.