I would guess it involves driving in pitch darkness without headlights, and whether there's a way to pull it off. Or it could be about testing certain folk-wisdom beliefs about driving at night or ways to improve your driving in the dark.
Once your night-vision kicks in I could see driving in the dark not being all that difficult, but certainly more difficult -and dagnerous- than driving with the lights on.
I spent ten years in the Army. I was an 88-M10. That means I was a truck driver. As part of your driver's training, you perform what is called blackout drive, which is essentially an entire convoy of vehicles driving in the dark on a moonless night. In some wartime scenarios, it's tactically sound to drive in blackout so as to not alert the enemy of your presence. In an urban combat environment, i.e. Iraq, it isn't used because you're driving on highways and the enemy would wait and then open fire on any vehicle they saw driving with the headlights off. The point is this : yes, it is entirely possible to drive in the dark with no headlights. I and many, many others have done so. So if that's the myth then = Myth confirmed.