We love this road. We've always cut across country from the motorway to Besançon because it's a joy to drive this stretch.
However tired you are, whatever the weather (once the snow was so bad we took a detour without realising), you just point the car and off you go, straight ahead until morning.
PS when we first drove this way, in 2002, there was no mobile phone signal at all. Now there's 4G 😀