My belated two cents... at first I also thought it didn’t make sense to leave the right-turning cars in the middle of the road till last – the current rule seems perfectly logical in that sense. However, the reason for the changes has been explained to me by those who know about such things and it also makes sense. Maybe more sense.
At the moment, a left turning car has to be aware of: cyclists to their left, pedestrians on the crossing they are turning into, right turning cars they have to give way to and cars behind them that are going straight through.
(Mauricio – from your posts, it seems like you think those cars going straight through are trying to ‘sneak past’ the left turning car. However, as far as I am aware, and how I was taught to apply the road rules by instructors, is that if you are ‘covered’ by a straight through car, which the right-turning car has to give way to, then the left-turning car is free to make the turn, provided there are no cyclists/pedestrians)
So at the moment, a left-turning car has to check for right turning cars on the other side of the intersection, check behind them on one side for straight-through cars that cover their turn, check the other side for cyclists, and check the crossing for pedestrians. That’s 4 different directions they have to look at once, hence the increased risk of crash.
Under the proposed system, the left turning car, while obviously still having to be aware of other cars, is largely free to focus on the direction they are turning. They have to check for cyclists to their left and pedestrians they might encounter, also to the left. Right turning cars have a better view of all 4 of the hazards I listed above, because they are all in the same vicinity and can be seen by scanning that section of the road, which is in front of them. The more freely left-turning traffic and the right-turning traffic being on hold also allows straight-through traffic to be more confident that a right turning car is not going to cross their path while the left-turning driver is hesitating about whether or not they need to give way to the right turning car (and in the process potentially missing a cyclist/pedestrian hazard as they are not looking in the direction they are turning).
And while the right-turning car may have to wait longer in some situations, any major/busy intersections should have a right lane/arrow to let them through first, before the rest of the traffic even has their turn. Otherwise, a little patience goes a long way, something most drivers seem to be sorely lacking in!
Crashes will still happen, but the idea is less will. Whether that pans out remains to be seen, and I’m still sceptical based on the fact that nobody knows how to apply the bloody road rules as it is!
However, having been a pedestrian in Australia for 2 months now, I can certainly tell you from that perspective that the rule works. Turning car drivers seem to be much more aware of pedestrians, and more often than not left-turning cars will wait for me to cross – I’m yet to work out if that is actually a rule as well, and they all should be giving way to me?
As an aside... as others have said, most people don't know the current uncontrolled T-intersection rules. However, learning to drive in Christchurch, this rule was drummed into me by driving instructors. There was a favourite intersection the licence testers used to love tripping people up and failing them with! They've since change the intersection now, not sure if they do this somewhere else instead now.