Anyone who is a fan of Bézier curves may appreciate this beautiful video by game-dev/educator Freya Holmér (24 min) https://youtu.be/aVwxzDHniEw
(I'm also a big fan of the much longer sequel: The Continuity of Splines
Thanks for sharing this, OP. I have the perfect friend to send this to, but I fear that it may do them more harm than good to find this near the end of our run (after they have spent many hours cursing trains)