I've had a single chip in the windscreen before, a couple of occasions infact, however, each time I've phoned the insurance company/windscreen guys the result has always been a replacement windscreen. This lead me to believe it's rarely practical to repair a chip, either that or it's a plan for the glass company's to get more money out of us/insurance companies.
Now if you've got a few chips and it's been repaired before it may well be it has to be replaced anyway. So before getting carried away why not go and see autoglass or someone like that? Even if you don't get the work done after them taking a look at it because you haven't spoken to your insurance company yet, it's worth getting someone in the know to advise you.
As for the stupid driver, he sounds like an idiot

but a stonechip could have happened anywhere at anytime.