I think most of us here are experienced enough to spot potential problems before they happen and take the appropriate evasive action.
There's a balance to be struck between riding defensively and riding assertively - that is, using your loaf, and showing other road users that you're not a pushover. I've found that if you're scared or intimidated, people seem to pick up on this and make your life doubly difficult.
So that's what you can do - what you can't do is legislate for the random actions of the careless/aggressive/half-witted. Of course it's horrifying and infuriating when a fellow cyclist is hurt or killed for no reason like this, but there's no sense in changing our behaviour (ie riding less) for fear of it happening to us. To paraphrase Ian Fleming, that would be 'paying a dividend to worry before it's due'.