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If Senator Robert Hill arrived home to a standing ovation from Howard government colleagues after securing the "Australia clause" in 1987, Greg Hunt is due at least a decent slap on the back from his Coalition mates.
The Environment Minister, who makes way for Foreign Minister Julie Bishop this weekend at the Paris climate summit, left satisfied he had delivered on the task assigned to him. 
Late on Friday night, after some last-minute wrangling, Hunt got what the Turnbull government had keenly sought: the acceptance of accounting rules that allow Australia unrestricted access to the 128 million tonnes of surplus emissions credits it claims from the first commitment period of the Kyoto Protocol.
That handy surplus will allow a big increase of emissions above current levels, and should the current upward trajectory of pollution breach the weak targets, Australia - once it ratifies stage two of the Kyoto Protocol - will get to tap international carbon markets to make up the difference.
At present prices, UN certified carbon units are selling for under $1 a tonne - a bargain compared with the $13.12 a tonne paid by the Abbott-Turnbull governments under its $2.55 billion Emissions Reduction Fund.
Hunt's success was to nullify opposition from tiny St Lucia in the Caribbean and South Africa to Australia's preferred definition of carbon emissions to include deforestation.
Had Australian negotiators not prevailed, the country would likely have struggled to meet the modest goal of cutting 2000 level emissions by 5 per cent by 2020. Excluding land use changes, the increase could be as high as 11 per cent, Melbourne University estimates.
As one negotiator for a major nation put it, thanks to Friday's deal, Australia can now lift emissions outside deforestation with little if any cost, at least to 2020.
Hunt secured the deal in part by "friendly and cordial" meetings with St Lucia's amiable Minister for Sustainable Development James Fletcher. He took to Twitter to share the success with colleagues, some of whom went nights with little sleep:
Deep congrats to our negotiators Peter Woolcott, Beth Brunoro & team for helping secure a global breakthrough on & passage of Kyoto 2 Rules
??? Greg Hunt (@GregHuntMP)      December 4, 2015
Advisors to St Lucia decried what they saw as "a continuation of the Australia clause".
That refers to the deal Senator Hill secured in 1997 that first allowed Australian emissions to rise 8 per cent during the first commitment period of 2008-12, while most other rich nations had to agreed to a cut.
Hill then held out an agreement until a special clause was added to the protocol to allow the inclusion of carbon emissions from land clearing. Since 1990 was a peak year for bulldozers in Queensland, the base was a high one. [As an added insult, the Howard government then refused to ratify the treaty - a position reversed when Kevin Rudd won office in 2007.]
With land-clearing restrictions in place, emissions from the sector fell sharply - allowing Australia to meet its Kyoto stage one targets easily. Hence that 128 million-tonne surplus, even as pollution from the rest of the economy continued to rise.
Other countries have surpluses too. Five of them - Denmark, Germany, the Netherlands, Sweden, and the UK - announced over the weekend they would cancel credits for almost 635 million tonnes as a gesture to help secure an ambitious climate treaty at Paris.
Australia, though, has not intention of forfeiting its credits, a spokesman for Hunt said.
"The Australia government has previously committed to do the same [as the five nations]," Erwin Jackson, deputy chief executive of The Climate Institute, said.
"Our current 2020 target is woefully inadequate," he said. "Strengthening our 2020 target though cancelling left-over emissions credits would close the gap between what we currently have on the table and what other leading nations doing."
The only blemish on Hunt's report card in the eyes of his more climate change-denying colleagues might be the concession Australia had to make to get St Lucia and South Africa to drop their objection to Australia's emissions definition. 
Australia will now be advocating, along with the most vulnerable nations to climate change, the inclusion of 1.5 degrees in the text of the treaty scheduled to be thrashed out by Friday within the warren of conference rooms at the summit site in Paris's northern suburbs.
As one negotiator put it, the Kyoto Protocol has been weakened to allow an Australian target that is effectively lower in exchange for consideration of a more ambitious global temperature goal than the 2-degree target agreed to by all nations at the Copenhagen summit in 2009.
On the face of it, the 2-degree target is enough of a long shot at Paris, so Hunt can sleep easy that his concession won't force the government to take any serious new action to curb emissions. 
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