The most unpalatable of theories, that the pilot crashed the plane deliberately in an insane act of mass murder, has become widely regarded as the most likely cause of the loss of MH370, which disappeared on March 8 last year.

Other pilots find this likelihood both shocking and compelling on all the evidence, and it was advanced by a number of people quite early in the saga, which cost the lives of all 239 people on board the flight from Kuala Lumpur to Beijing in a Malaysia Airlines Boeing 777-200ER.

The most refined of such theories was set out in this article in Flightglobal by David Learmount, based on the calculations of Captain Simon Hardy. It has gradually grown in its acceptance. It may well be tested by the Australian-led ocean floor search for the wreckage upon the completion of the current priority search in May, when Malaysia, China and Australia deal with the “what next” issues, should the priority zone not turn up any wreckage.

However, none of those parties has said anything official about the Hardy theory turning into a firm search target, even though it nominates a probable location for the jet within the larger, non-priority search zone, in fact only around 160 kilometres from the nearest part of that priority zone.

This past week, most of the talking was done by Australia, first by the minister responsible for aviation, Deputy PM Warren Truss, who backtracked on an interview given to Reuters in which he said Australia was going to stop searching for the wreckage. Then Prime Minister Tony Abbott more or less ran right over those tracks by essentially confirming the tenor of the Reuters report. In short, Australia was and then wasn’t and now is determined that the search will not continue at its current costly intensity if nothing is found by about late May.

The enormity of the suggestion that MH370 captain Zaharie Ahmad Shah meticulously planned this atrocity, and by inference killed the passengers through a cabin decompression and performed a three-point sentimental farewell fly pass of his home island of Penang before taking the jet to a place where he thought it would never be found, remains totally unacceptable to members of the airline pilot community in general.

That is understandable. The theory, if true, might also explain why the Malaysian authorities and government figures were so determined to lie to everyone about what they knew as to the likely cause of the disappearance on March 8, 2014.

However that doesn’t explain why the flight was allowed to depart that morning, nor the bizarre neglect of duty by the country’s air force in watching what was happening on military radar and doing nothing about it.

Or maybe it does? Maybe the authorities had non-specific information, failed to order a mass grounding, and found out the terrible truth 42 minutes after MH370 took off, when its air traffic control transponders suddenly went dark.

Clearly one of the risks in the Hardy scenario is that it feeds much downstream speculation as to who knew what and when, and who made what decisions, in the face of such a situation.

On the other hand, it eliminates conjecture about the jet that involves layer upon layer of improbability, such as Russian plots, a US military shoot-down, the theft of tonnes of gold bullion, and even a clandestine burial in the vastness of the Baikonur cosmodrome in central Asia.

It just leaves the Malaysian authorities with the shame of inaction and lies.

The other risk, which Hardy acknowledges by inference, is that some terrible doubts remain over the quality or accuracy of the Inmarsat satellite data and its analysis, where even the slightest of errors in assumptions, or the hard data to which they were applied, could result in the calculations being more than a few hundred kilometres out.

Hardy’s work may contain errors that actually place the jet inside the remaining 57% that is unscanned in the priority search area, but toward its south-western extremity, more than 2600 kilometres from Perth.

Thus the searchers may have reason to think that both Hardy, and their search advisers, are right, and that the moment of discovery by the current search is drawing nearer.