What about during peak traffic hours in the city? Keeping left (instead of choosing the lane based on destination) will most probably slow down traffic IMO.
The road user rule has an exemption for congested roads
A driver may drive in the right lane in the direction of travel when driving on a multi-lane road if—
(g) the traffic in all other lanes is congested; or
(h) the traffic in every lane is congested
I don't really get the need for this distinction. City driving is completely different to highway driving because of the 50k speed limit, which doesn't leave any room to lane switch and legally overtake anyway. What harm am I doing if I sit in the middle or right lane for the duration of my journey down, for instance, Greenlane/Balmoral Rd, whether or not it's congested?
apart from breaking the law:
You are causing the person who wants to pass you to change to the left lane/ weave through traffic.
if you are beside even one more vehicle traveling at the same speed the person behind can't pass
and of course if you use the "I'm not causing anyone any harm so I should be able to do what I like defense" this means you should be able to do the following:
not indicate if you can't see any other traffic
go through red lights if you can't see any other traffic
drive your car without a licence, as long as you know how to drive
drive at 130km/h on empty roads
I would like to do all of those things...but I don't (much) because If I want the rights/benefits of our modern society I also need to follow the rules.