MixedFraction

There's a huge difference between stopping on the highway and decelerating due to lack of engine power. The driver knew what was happening, turned on his hazard lights, and didn't apply the brakes. Slowing down on the highway, although annoying, shouldn't be an unfamiliar or unsafe scenario (ex: construction, traffic backup, etc.)

This would be a completely different story if the researchers applied full force to the brakes or accelerator since those are unexpected (to other drivers), sudden, and difficult to react to behaviours.