> But how about a dial that stops turning at the minimum and maximum
That, too, is mentioned in the article ("This means you can simulate different types of haptic feedback, like different detent strengths and hard stops.").
> and doesn't need you to take your eyes away from the road at all?
Also addressed in the article ("Showing three different data types in one dial is possible but definitely the maximum. When adding a fourth function, keeping track of your position in the interface without looking down becomes too difficult.").