We might speculate that growing trends of "medicalising" the ageing process and also reflexively ordering swathes of imaging and pathology are part of the problem. But there is one other cause that surely isn't speculative: the behaviour of practitioners in the specialist medical sector.

One Canberra specialist is charging $360 for the initial consultation, which seems to occupy not much more than 20 minutes, and qualifies for a $70 Medicare refund. The same doctor charges $220 for all subsequent visits, which are about 15minutes' duration, and qualify for a $30 government refund.

When doctors become a problem by rorting "the system" for all it's worth, action must be taken. Is the government really so frightened of the AMA that it is trading away the common good to the soaring demands of these profiteers?

Ross Kelly, Monash

The concept of opportunity cost is one of the great contributions of economics. For the cost of one submarine, we could either fund Gonski for six years; or reinstate the whole of the recent foreign aid funding cuts; or retire around one-quarter of all HELP student debt; or build around six new hospitals; or reduce the current Budget deficit by one-third.

If you wanted to be really generous, $1000 could be given to every taxpayer. That's just one submarine. Imagine what could be done if none of the 12 were purchased. It's all about choices, and Australians deserve to be better informed on just what those choices are.

Rod Price, Jerrabomberra, NSW

The 2016 Defence White Paper issued last week contains this paragraph: "Climate change will see higher temperatures, increased sea-level rise and will increase the frequency and intensity of extreme weather events. These effects will exacerbate the challenges of population growth and environmental degradation, and will contribute to food shortages and undermine economic development."

Logic demands that this would require greater spending on means to mitigate climate change (such as support for renewable energy), on family planning (given population growth is deemed a "challenge"), on the Green Climate Fund (to help developing countries adapt to climate change), on agricultural research (to maintain yields as temperatures rise), and on overseas aid generally (to enhance economic development).

What is the government's response? Increase defence spending to 2 per cent of GDP, including acquiring 12 submarines. It will no doubt cry poor when it comes to funding the above.

Jenny Goldie, Michelago, NSW

I ask George Pell and his supporters to explain to me in relation to child rape how "they were different times".

Weren't these the same times the Church was demanding state-initiated punishment for extramarital sex, homosexuality and teen pregnancy?

Wasn't the Church harassing and scaring children over masturbation?

When was it ever fine to rape children?

John Murray, Ben Bullen, NSW

NSW's Judy Kelly (Letters, February 2), who thinks Cardinal Pell is "sitting like an obdurate cane toad in Rome on day two of the Royal Commission", claims the cardinal "has shown not a shred of empathy, compassion, feeling, or discomfort". How did Judy arrive at that conclusion? Is she able to delve into a person's heart and mind, and make a judgment?

Henk Verhoeven, Beacon Hill, NSW

Henk Verhoeven (Letters, February 24) complained that it was wrong to compare Australia's off-shore refugee detention centres with the Nazi concentration camps and the Soviet gulags.

And yet, in a letter published in The Age on March 3, he finds nothing wrong with comparing Cardinal Pell's questioning by the Royal Commission under due process of law with "the worst form of an inquisition".

Methinks the man is being selective about making comparisons.

Rajend Naidu, Glenfield, NSW

It seems to me that the important message in Peter Martin's article "GDP: Game changer. Economy picks up as income dives, budget weakens" (smh.com.au, March 3) is that nominal GDP growth remained "extraordinarily weak", with no expected increase to government revenue.

If government revenues don't increase, does this not imply that there is no meaningful benefit to the country, as government revenue is supposed to reflect actual economic activity (other than tax avoidance).

Clearly there is something wrong with the measure of growth being heralded by the government, especially when personal spending is being propped up by an erosion of personal savings which can only serve to weaken the ability of individuals to self-fund their retirement.

Dr Bradford Sherman, Duffy

The Coalition and the Greens are proposing changes to the senate voting procedures, and seeking to ram these changes through Parliament before the next election. They use as an argument that it is not democratic that people like Ricky Muir are elected as senators with as few as 479 first preference votes.

Senator Muir actually received more first preference votes than three LNP senators who were elected at the same time – Matthew Canavan (Qld, with 325 votes), Michaela Cash (WA, with 349 votes) and Linda Reynolds (WA, with 325 votes).

At the 2013 elections, the major parties (LNP, Labor and the Greens) received 75 per cent of the votes, but achieved 85 per cent of the senators elected. So, 25 per cent of voters supported the minor parties, but received only 15 per cent of the senate positions.

The government and the Greens have an interesting definition of democracy. All they are doing is seeking to entrench their own positions, without community consultation. The LNP and Greens connivance on senate voting changes have nothing to do with the democratic process.

Australia should be thanking the independent senators for saving the country from the worst excesses of the Abbott government.

R. King, Melba

Brendan Lyon ("Liberals have to get over their unhealthy obsession", Times2, March 2, p5) thinks that the ACT Liberals should ignore the facts and drop their opposition to the Capital Metro – this from a paid booster for the construction industry. In contrast, Kent Finch ("Why the ACT needs to hedge its public transport bets", Times2, February 26, p5) uses evidence and insight to make a clear and compelling case to put the tram on the backburner.

As he notes, there are truly transformative new transport technologies on our doorstep, and we should wait to see where they take us before embarking on an option that is otherwise inflexible, costly and largely irreversible if it is ultimately found wanting. Fools rush in, as they say, and we would be doubly foolish to listen only to the deeply vested interests of the construction lobby.

Vernon Topp, Kaleen

Brendan Lyon seems to be acting as a mouthpiece for ACT Labor. The ACT government decided in its business plan (October 2014) to shoulder the revenue risk for the Gungahlin tram so the selected consortium couldn't lose financially. If the tram's patronage is lower than the projections, ACT ratepayers will be called upon to ensure the tram consortium gets the promised return. You can't blame the consortium for signing up for a low-risk investment, but we should all ask why, if the Gungahlin tram is such a great project, did the ACT government decide ratepayers should shoulder the patronage/revenue risk?

Bill Crawshaw, Fadden

I'm disappointed you published advocacy by 350.org in your news section ("Heat puts reef at risk of bleaching", March 2, p5). It belongs in the opinion section.

Allow me to correct Russell Reichelt's misinformation. Corals bleach naturally under a variety of conditions. They consume their symbiotic algae often for a host of reasons.

Corals are resilient and have existed and evolved through 400 million years of stress.

Furthermore, Mr Reichelt's pointer to a higher authority is irrelevant. NOAA is under investigation by Congress for data-fiddling. Australia's BOM should be queried too.

Gerry Murphy, Braddon

Kate Morris (Letters, February 28) canvassed the subject of blood alcohol testing in public places. I have been trying for 17 years to convince the ACT government that clubs, bars and pubs should have an Australian Standard self-testing unit on their premises. This would allow the public to test themselves as well as assisting those who serve alcohol to meet requirements for the responsible serving of alcohol.

Unfortunately those against introducing such equipment are referred to as "vested interests". The recent NSW/ACT Alcohol Policy Alliance paper being studied by the ACT government states, "consideration should not be given to mandating alcohol breath-testing units. While this measure may assist in determining a patron's intoxication levels it should not be seen as a harm reduction measure". Why then do the police remove a driver from the roads if they return a BAC reading of over .049 if it is not to stop harm. The NAAPA report gives the government a reason for doing nothing.

T. Toohey, Crace

LEY'S CLAIM A HOLLOW 'WIN'

According to the Reserve Bank of Australia, inflation between 2002 and 2015 averaged 2.6per cent a year and is now around 1.5per cent. So why would Sussan Ley claim a "win for consumers" that health insurance rises are now 4.1per cent above inflation, compared to the average between 2002 and 2015 of 3.5per cent?

Kent Fitch, Nicholls

INCREASE OK FOR SOME

In today's economic climate, only a politician whose salary has risen by more than 5.6per cent in the comparable period would consider that amount to be a reasonable rise for health insurance premiums.

Phil O'Brien, Flynn

CARDINAL SHOULD RESIGN

Cardinal Pell refuses to accept any responsibly for decades of Catholic child abuse, and now has dug his own grave by saying that child abuse was of "not much interest to me." The Greeks have a saying that applies to Pell. "A fish rots from the head down." Pell should resign. Failing that, Pope Francis should defrock him for moral depravity.

Graham Macafee, Latham

DELAY SIGNING CONTRACTS

If Brendan Lyon ("Liberals have to get over their unhealthy obsession", Times2, March 2, p5) is so concerned about supposed sovereign risk he would advise the Capital Metro consortium to hold off signing any contracts until the next election. That would give them the certainty they desperately crave.

Gordon Williams, Watson

WRONG FIT FOR MORRISON

Unfortunately "Stop the deficit" is not as simple as "Stop the boats". Making Scott Morrison Treasurer is like making the captain of the football team the captain of the debating team. Different skills required. Caveat: Not all football players are David Pocock.

Peter Edsor, Bungendore

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