What is the function of the 'Eco-Roll' (freewheel / coasting in neutral) mode found in modern automated commercial vehicle transmissions?

1. On slight downhill slopes or flat roll-out phases where engine braking is not required, the transmission shifts into neutral to let the vehicle coast without engine drag, keeping the engine idling at minimal fuel consumption to preserve kinetic energy
2. It cuts off fuel injection completely while keeping the transmission in 12th gear to brake the truck on steep descents
3. It automatically disables the ABS system to save battery power
4. It locks the differential to increase traction at high highway speeds