Mercedes' Drive Pilot seems to be in operation like many other "traffic jam assistant" technologies already on sale today, but there's a key difference: Once you engage Drive Pilot, you are no longer legally liable for the car's operation until it disengages.

Mercedes' willingness to accept liability for its semi-autonomous vehicles will surely help its chance of satisfying various regulators, removing driver responsibility required massive technological improvement over existing Level 2 systems. Drive Pilot is designed to give drivers a 10-second warning before switching off, and has more redundancies, with additional power supplies to critical systems.

Mercedes' Drive Pilot is the first semi-autonomous system that is not leaning on the crutch of beta test or relying on the constant vigilance of a human operator, but Drive Pilot was smoother and more competent than any other semi-auto driver aid. The only snag was that the vehicle picked up on amber lights and confused them for emergency lights, prompting a 10 second warning and manual take-over.