Commentary on rail options in Sydney continue to mention a preference for a "European-style metro system".
I want to know what kind of rail system this is meant to be describing. Typically rail is described as "light" (like trams - think the light rail to Glebe)or "heavy" (which incorporates all the rest of the passenger and freight rail networks). Fundamental differences relate to the number of carriages, the kind of inclines they can handle and the frequency of service.
As far as I can tell the proponents of "metro" are really talking about the same thing as Asians would call a "rapid transit" system. Its features are, typically;
1. Carriages designed mostly for standing not sitting.
2. Carriages with lots of doorways for speedy exit and entry - some systems use one side of the train for boarding and the other for alighting.
3. Very frequent trains.
Sounds awfully like the early rail carriages I was still riding as a school boy with four doors per carriage. Then some idiot decided to deal with the congestion problem at city stations by building double deck trains - which are idiotic beasts that are impossibly slow to load, have very little functioning standing room (compared to any single deck carriage I have ever ridden on except for amn intercity style train).
So Sydney can be converted to a "metro" on this definition if we simply change the trains - and do something about creating another line through the city and/or improving the platform functionality at Wynyard and Town Hall (e.g. can we use both sides of the train at Wynyard? Could the Eastern suburbs line be dropped lower at Town Hall and have three sets of dual lines not two sets of three? Or perhaps could the city circle be rerouted under Town Hall and not stop there at all?)
The original North-West rail plan met many of the requirements, including a new Harbour Crossing. Let the engineers get on with it.