"You sure know how to wreck an afternoon's skiing," the former Liberal premier joked, trying to make light of the deep disappointment he felt at Baird's abrupt departure.

"Mike has always said he was not going to stay forever, but this is sooner than I would have expected," Greiner later told Fairfax Media. "I just hope it doesn't stop [other] policy-oriented or non-professional politicians from having a go".

Just before Christmas, Greiner told Fairfax that Baird was "far and away the outstanding political leader in Australia today, state or federal".

He saw in the younger man some of the same qualities he had brought to his own controversial tenure as NSW premier between 1988 and 1992.

Both were do-ers, in Greiner's eyes, willing to take sometimes crazy-brave risks for the sake of driving change, and damn the political consequences.

Baird had made a similar point at an appearance at the National Press Club in Canberra at the end of November, when he said: "There is no point in having political capital unless you spend it. You can do nothing, but then what a waste! ... You have got to be prepared to try and fail".

Baird's parting press conference detailed his successes, with budget repair, the sale of poles and wires, infrastructure and jobs creation given top billing. But there were controversies and failures - most notably the handling of the greyhound industry ban and council amalgamations.

These were instances of what Greiner calls the "anti-politician" coming out in Baird, who had been a high-flying investment banker before becoming an MP.

"He is not a political animal, he has not spent most of his life between university and the age of 35 in politics," Greiner points out. "Broadly, that is both a plus and a minus. In retrospect I would say the same about myself; its very much a two-edged sword because all those virtues people can turn into negatives."

"One conclusion that might be drawn is that the anti-politician type can't hack it, doesn't like the fire [but] it would be a shame if people drew that conclusion. I hope that if people look at his manifest successes, it should not discourage anti-politicians from having a go"

A senior Liberal observes that although Baird was born into a political family (father Bruce was a former state minister and federal MP) "he is not by his inherent nature political".

"There has been a bit of internal criticism that Mike does not have that sixth sense ... but it is one of the things that made him very authentic."

Some suspected late last year that Baird's resilience was wearing down, the source said: "Maybe until greyhounds Mike Baird, the wunderkind, had never lost a battle. Maybe there was a bit of a glass jaw."

Greiner believes Baird showed real political courage in trying to put a GST increase back on the table as part of a "grand bargain" that would have included company tax reform and more funding for health. It perished at first base with his Canberra colleagues.

"Those ideas were clearly in the national interest" says Greiner. "He had a level of frustration [with Canberra] at the lack of action on broad-based tax reform and on federalism."

"Malcolm Turnbull got sucked into the usual let's pick this off and let's pick that off"

At his parting press conference, Baird alluded to the stalemate on tax and federalism as perhaps his greatest regret:

"There was a big opportunity there to do something very significant in terms of competitiveness of the economy and the sustainability of funding services in the long term. I'm disappointed - I gave it a crack but that was something that wasn't to be," he told the state press pack.

Greiner said Baird had left NSW with a "substantial legacy" in the form of the "best budget and infrastructure situation in Australia".

But politics moves on swiftly. Asked how the party would be reacting to the shock of Baird's departure, Greiner replied: "I imagine, it's the king is dead, long live the king."