I had a very different experience. One week after I bought the car in the UK, I was driving between Dunkerque and Lille and when I overtook some lorries in the slow lane, I had a sudden, ACC instigated heavy braking, at about 80mph! It put the sh**s up me!.
True, after I had had this a couple of times and pressed the accelerator hard a couple of times, it did seem to learn. The first time, when I wasn't expecting it was frightening, so BE VERY AWARE!