The answer to drunk driving is cheap, safe, reliable public transport.
In South Africa? Where many middle-class generations have grown up with a culture of "Public transport? In South Africa? You must be mad." I don't see that happening even if such an eventuality arose.
People who want to drink and drive will do so regardless. This is exactly why countries with world-class public transport still have drunk drivers. Though you might argue that there are fewer, that may well be true.
What I do know is that people make a choice when they climb into their cars with the intention of going to a pub and having a few drinks. They know what they are planning to do, and they are aware that it is dangerous for themselves and those around them and this is long before anyone can argue that their judgement has been impaired by drink.
It isn't much different to sitting in front of Pick 'n Pay playing with a loaded gun: you know it's dangerous, you know it's not allowed for very good reasons, but you're doing it anyway.
The only thing that will ever do anything to deal with drunk driving is when people take responsibility, grow up and stop acting like snot-nosed brats who think drinking is "cool."
Adults don't need to drink to have fun, and adults certainly don't hop into a car and drive around drunk.
But then, unfortunately "adulthood" doesn't necessarily bring an adult mindset to the table.
Driving drunk is premeditated the moment a sober person picks up a drink knowing that they'll be climbing into a car afterwards.
As far as I'm concerned, if someone gets harmed by it, it's murder.