I was in the left lane of a divided highway today. 55 mph zone; I was doing 60. The car in front of me suddenly swerves to avoid what turned out to be some cardboard boxes in the road. Before I realized what was happening TACC was slowing, presumably because of the boxes. I took over auto steer and swerved around the boxes as well. Now, had I hit the boxes it wouldn't have been a big deal. But had this been some other kind of hazard it could have caused some serious damage. The slowing gave me the time to maneuver around the boxes without having to make any sudden movements. It definitely gave me more time than I would have had if I had to notice the obstacle myself. This is the first time TACC slowed for me for a non-automotive obstacle. It could have been a false positive (mistook the boxes for the car I was behind) or it could have been by design. Has anyone experienced something similar?