As big and loved as they already are and will be,Sydney’s three new metro rail lines which are under construction will still not come anywhere close to overtaking the existing double-deck train system in terms of the volume of passengers they move when the last of them is opened in 2032.

The big question is whether the latest review will trigger substantive improvements at Sydney Trains.

Premier Chris Minns has made clear for weeks that the heavy rail network was desperately in need of some love,besides the fact that building extra metro lines was hugely expensive,and the state waslimited by what it could afford.

As the Schott review demonstrates,money is sorely needed for the heavy rail system.

While paling in comparison to the billions of dollars the state is pouring annually into building the new metro lines,an extra $100 million-plus a year for the double-deck train system will go some way towards reducing the risk of another crippling incident similar to what occurred in May.

Yet throwing (some) new money at the problem does not guarantee a fix to a highly complex system,which can be severely disrupted by factors sometimes outside its control.

Some of the problems identified at Sydney Trains are cultural problems within a bureaucracy which has a habit of sticking to its old ways.

As Transport Minister John Graham said on Tuesday:“I want to make it clear,this isn’t just an investment problem – there are cultural issues here. The investment by itself won’t be enough.”

A review – as hard hitting as it might be – is only as good as its follow-through.

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