The success of the car-lite campaign requires sweeping policy changes ("Can S'pore go car-lite?"; April 18).

Here are a few key considerations.

One, can Singapore afford to forgo the revenue generated by private vehicle taxes, certificates of entitlement, road pricing and tariffs on fossil fuels?

A shortfall in state revenue might compromise its ability to fund improvements in other areas of transport infrastructure.

Two, is the goal of shrinking the overall vehicle population truly compatible with the Government's other major long-term target, that of increasing the population of Singapore?

Granted, considerable effort has been made to expand the MRT system, grow the fleet of public buses and construct new roads to accommodate more people.

Nevertheless, existing arterial transit corridors have seen only marginal improvement, and congestion remains a pressing concern. Neither private nor public transport has been able to keep up with growing numbers of road and rail users.

Three, will public transport improve to the extent that it can supplant private cars for the majority of journeys?

Personal vehicles allow the driver to move point to point without the hassle of transfers or further walking. They can be used on demand rather than at the mercy of a schedule, and are also perceived to be less susceptible to technical faults and major delays.

Taxis, hired vehicles and public-use autonomous vehicles might help bridge the gap, but again, they are unsatisfactory solutions.

In the case of taxis and hired vehicles, regulations remain poorly defined, and fare structures are commuter-unfriendly.

The adoption of autonomous vehicles has in general been painfully slow. It will be some time before a fleet of sufficient size enters regular service, if ever.

Paul Chan Poh Hoi