By Richard Black
Environment correspondent, BBC News website
Two nights of inflamed passion in the Balinese heat should be enough to excite anyone.
A group of "sceptical scientists" demonstrated, calling for less action
So it would be a churlish delegate indeed who professed disappointment as he or she staggered a bleary route from the conference hall to the taxi rank, ready for some home comforts after a marathon two-week session.
This has been a harsh round of UN climate talks.
Previous rounds have seen governments accept commitments they were never going to be able to meet - witness the US signing of the Kyoto Protocol a decade ago in the teeth of Congressional opposition - and all were aware of the domestic political consequences of getting this one wrong.
For Europe, already committed to unilateral emissions cuts of 20% by 2020 and prepared to go further if others joined in, the grail was to leave Bali with the US, Japan, Russia and the rest of the industrial world signed up to big cuts.
The US and Canada, on ideological grounds, and Japan because it is already struggling to meet its Kyoto Protocol targets, were determined to avoid anything firm now.
If no-one leaves Bali with everything they wanted, it is also true that no-one leaves without some kind of present
For varying reasons, most industrialised nations wanted the major emitters of the developing world - China, India, Brazil, South Korea - to accept the principle that at some point, they would have to come on board with numerically-defined emissions curbs, too.
Fearing economic consequences, and citing the UN convention's declaration that nations had "common but differentiated responsibilities" for climate change, those major emitters were determined not to give too much ground.
Meanwhile others - drought-ridden African countries, and those likely to be erased from the geographical and political maps by rising sea levels - wanted the rich West, which has built its wealth largely on the back of coal and oil, to pay for the effects of the pollution they have caused and from which they have benefited.
In retrospect, does it seem absurdly ambitious that negotiators tried to cram all of these demands into a single document, the "Bali roadmap"?
The Indonesian hosts partly gained what they wanted on forests
Perhaps. And there will be voices now, as there always are, condemning the UN process for being bulky, ponderous, unwieldy, bureaucratic, and bound by the lowest-common-denominator-generating demon of consensus.
But if no-one leaves Bali with everything they wanted, it is also true that no-one leaves without some kind of present for their political masters back home.
Europe has not got what it wanted. But it does have a document committing states to the principle of further emissions cuts, and to concluding negotiations on those cuts by 2009.
The date is important, because if concrete targets are established going further and deeper than those in the Kyoto Protocol, governments and businesses will need time to adjust to them before the current protocol targets expire in 2012.
However, the EU must concede - and some European delegates did concede - that they have got far less than they demanded.
The Bush administration is not for turning.
Environmental groups accuse the White House of blockage and betrayal and obstruction.
Al Gore was the most savage critic of the Bush administration
But it is difficult to accuse it of inconsistency. In Bali it deployed positions and tactics which were totally in keeping with previous years.
And there is a case for saying that Europe played a poor hand here, demanding something it was never going to get.
Its counter-arguments are that it proposed targets based on the latest scientific findings from the Intergovernmental Panel on Climate Change (IPCC), which the US, Canada, Japan and so on have all endorsed; and that it needs to confront opposition in those other nations, not just in the US.
Given Japan's enthusiasm for the Kyoto accord, its stance here must have hurt.
At home, the US administration has been keen to promulgate the politically convenient view that climate change is now really China's fault; hence the desire to wring some kind of commitment from the Chinese.
The US talked tough, but in the end got less than it wanted. However, as its demands fell well short of binding numerical targets for China, the White House spinmeisters should be able to garnish its last-minute volte-face with glitter.
Developing countries gained less access to clean technology than they asked for. But there are various multilateral and bilateral deals outside the UN climate framework that may be more relevant in this area anyway.
And protecting the poorest nations? Like the emissions goals, money for adaptation is largely theoretical at this stage.
The Bali roadmap envisages expanding the Kyoto mechanisms designed to leverage money from international carbon trading to pay for sea walls, fresh water infrastructure, new crop varieties, mosquito nets and whatever else may be needed as the world warms and rainfall patterns change.
Bali's beaches provided a luxurious environment for the talks
But the funding is not yet anything like sufficient - nor is it clear that it will be. Efforts to help Africa adapt "have centred more on seminars and workshops rather than demonstrable pilot projects," Nigeria's Environment Minister Halima Tayo Alao told delegates.
The forests agreement also fits into the "pending" file. Though opening up the principle of rewarding poorer countries for protecting their carbon-storing trees, much remains to be worked through, inside and outside the UN process, before the dollars, euros and yen begin to flow.
Long road to Copenhagen
So now the map leads to Poznan in Poland in a year's time, and to Copenhagen late in 2009 - the scheduled final destination on the Bali roadmap.
Already it is possible to identify important staging-points on the path to Poznan.
The first is the Honolulu meeting next month of the "major economies" or "big emitters" group set up by the Bush administration that includes 16 major producers of greenhouse gases.
Will EU members arrive demanding to discuss numerical targets? Will the US stage-manage events for a domestic audience as it did at the group's inaugural meeting in September?
EU leaders say they want to be negotiating the Bali roadmap by April. Targets, commitments from major developing world economies and adaptation funding will surely emerge then, even if they are kept under wraps in Hawaii.
Halfway through the year, the Australian government will hear back from its hastily-assembled expert committee on what it should commit to.
Kevin Rudd's new government has an influential role ahead
Though arriving at the Bali meeting bearing papers ratifying the Kyoto Protocol, incoming Prime Minister Kevin Rudd disappointed some observers by refusing to back firm targets.
The committee's report and the government's response to it will decide if Australia re-enters the Kyoto camp with the zeal of a reformed smoker or the reluctance of a cat forced to bathe.
Finally, and most importantly, comes the US presidential election.
As Eliot Diringer, director of international strategies at the Pew Center on Global Climate Change in Washington DC, commented: "For us, the really critical test [of the Bali agreement] is whether it provides an opening that a future US administration can come in under, and for us it meets that test."
What would a Hillary, a Barack, a Mitt or a Mike in the White House do with the roadmap?
Do they even have time to consider the question as they track from handshake to handshake on the vote-garnering trail?
It is the issue that more than any will determine whether the Bali road trip ends safely in a warm hotel bed, or in steaming wreckage deep in a dung-filled ditch.