What's with the Traffic Lights on Freeway On-Ramps?

[Mulva]

Not sure if this is Vic or NSW or both - watching dashcam videos on YouTube I notice one or both states has fast-cycling traffic lights on some freeway on-ramps. Think it is one car is meant to go through per cycle.

What is the deal with that? Is that to try to manage congestion? Is it to try to help people merge better - as in the bottle-neck is moved back from the actual merge point, so by the time cars that are let through get to the merge they are up to freeway speed (rather than have bottleneck of cars stopped on the ramp at the actual merge point, where they are trying to merge from a standstill with traffic that is doing highway speeds)?

Does it work? From the videos I've seen it doesn't look like many people pay attention to them (but then I appreciate thousands do and dashcams just shows those that don't).

I probably don't understand the need due to living in Adelaide, where you guys reckon our peak hour is when both cars are on the road at the same time.