Faster than the wind

Saw some article in PopSci about a wind powered car, and it used a propeller to drive the drive wheels. Claimed it could drive directly into a headwind with the setup. Which makes sense, but then we later began discussing whether it could go fater than a tailwind. Very non-intuitive, but turns out this is possible… and pretty dang cool. I did some searching and found this discussion on the topic: (dtfttw = downwind faster than the wind)