Pitbull
Verboten
The thing you are forgetting is that ALL of those alternative routes are already at capacity. Putting ALL of the traffic onto back roads that already carry a significant amount of traffic is just not going to work.
Have you ever seen what an intersection on a side road looks like because all the traffic has been diverted off a highway due to an accident or temporary closure? Now imagine that at ALL the intersections on ALL the backroads in Gauteng. It's just not going to work.
And what happens when there is a blockage up on one road, or an accident? You can't divert traffic around it like you do on a highway. It just blocks the entire road. Then the intersections around the accident get blocked, then you have gridlock.
Seriously, I think you need to talk to some traffic management specialists here. Cos your idea is seriously naive.
If the N1 was to be removed tomorrow sure it would go grid lock for a day or 2. Eventually people will get their travel times right and it would flow as normal. The reason you get grid lock traffic when something happens is because no one planned for it. You know that...