I'm not sure why Victoria is so strict - all the Victorians I know sit 10km/h under the speed limit because of this - it's so easy to get into a bookable speed zone unintentionally there.

If you think about it a 2km/h leeway which increases to 3km/h over a certain speed I think either over 80km/h or 100km/h I'm not sure isn't really sufficient.

So the reason for the higher speed tolerances in NSW is because the government doesn't want to encourage speedo watchers which is bloody dangerous.

The fact that the speedos read under and the tolerances they give for example i did 125km/h on the speedo in 110km/h zone, GPS reads 117km/h or so. Then the margin of error brings it to 114km/h or so and the not publicised but roughly 10 percent leeway brings it down to 103km/h. But as a note it's YMMV I can't guarantee 100 percent with the leeway as I'm not a copper.

But to speed in NSW you have to be actively trying or just careless. And like I said that's just with the cameras.

Highway patrol like I said only really pull over the excessive speeders, they really don't bother for someone 10km/h over as they know someone will come along in 2 mins doing something like 20km-30km/h over. I see it regularly on the highway. If they pull over the 10km/h guy it cost them the 20-30km/h booking and also they have to reset which costs them more time.

But in Victoria they seem to like to book everyone. I've only been there once and apparently they're notoriously known for doing that and being the only jurisdiction to have such strict rules.