That is a problem isn't it? For human drivers seeing a line of cars drive 20 over the speed limit almost always makes us follow herd instinct and "keep up with

That is a problem isn't it? For human drivers seeing a line of cars drive 20 over the speed limit almost always makes us follow herd instinct and "keep up with traffic" even if it's technically illegal. Something a self driving car (I presume) won't do. The problem is entirely on the human side though and needs to be solved there.