A few people have suggested there must be more to it, but having been on the receiving end of an unprovoked attack, I know it happens and it's a certain type of person that does it. The concern from me is the number of offences and reports from people about his attitude and behaviour. If it had been just a single event, he'd done his pennance and it was a while ago, I wouldn't have quite the concerns I do. You are right, a public apology and statement of intent would help a lot - even if it might not be completely believed - but as far as I'm aware, he's never done that, which isn't good either.