The reliability of MRT trains is an engineering problem, so let the engineer solve it in "the engineer's way", Transport Minister Khaw Boon Wan said in Parliament yesterday.
Commuters, commentators and armchair critics should just stick to tracking outcomes, such as "when I need a a train, is it there?", he added.
The minister was responding to Non-Constituency MP Dennis Tan's detailed questions on whether there are parts in the MRT system that are operating beyond their expiry dates.
Mr Tan also asked if the Government would publish key performance indices (KPI) to "measure parts replacement and maintenance works".
Mr Khaw said the "manufacturers' recommendation is just a reference, a guide".
So if you publish for each item when are you going to replace this, etc, I think it will be such a mass of data that I don't think it conveys any information.
TRANSPORT MINISTER KHAW BOON WAN, explaining why tracking rail maintenance is possible but impractical.
"In fact, we have gone beyond this. It is just no longer a case of, well, just replace those parts because manufacturers say Year X.''
He added: "We are now going into a situation where many of the parts... are being replaced not because they are going to reach (their expiry dates) or about to expire but because of obsolescence."
As for KPIs for track maintenance, he said this was possible, but impractical.
The reason: The parts in one train depot run into "five digits", and there are "tens of thousands of components".
"So if you publish for each item when you are going to replace this, etc, I think it will be such a mass of data that I don't think it conveys any information."
It was best to let engineers do what they need to do to make the system reliable again, he added.
"We are not quite where we want it to be but we are making improvement", he said.
"This is a top priority for myself, for my ministry."