Jesus if we're going to be hung for every mistake
A mistake is having to brake a bit more heavily than you expected to.
The point is it was an avoidable error made by someone travelling too fast for either their skills or the conditions. He seems to feel it was 'just one of those things'. It wasn't he caused it. The fact there weren't more serious results for either him or the other people was down to luck.
Peoples road safety shouldn't; be down to whether another user is feeling lucky on any given day.