Perhaps it never did but what definitely made it worse was the politicised meddling of the Obama administration.
Before the report's formal release, US officials - who had seen an earlier draft - wrote to the United Nations demanding it be amended.
"The discussion of the economic costs of mitigation is too narrow and does not incorporate co-benefits of action."
Loosely translated this means: "If we admit how much we're spending to such little purpose, the taxpaying public is going to kill us."
So the report was duly amended to suggest that the benefits of wind turbines, solar panels, biofuels - not to mention the losses entailed by leaving fossil fuels in the ground - more than offset the massive costs and inconvenience involved.
This presumably is why the left-wing Guardian was able to give its coverage the headline "IPCC climate change report: averting catastrophe is eminently affordable".
Catastrophic climate change can be averted without sacrificing living standards according to a UN report, which concludes that the transformation required to a world of clean energy is eminently affordable.
“It doesn’t cost the world to save the planet,” said economist Professor Ottmar Edenhofer, who led the Intergovernmental Panel on Climate Change (IPCC) team.
Perhaps this was an accurate summation of the report if you read it a certain way. But equally, it was accurate to report, as Breitbart London did, that it was basically a wish list for the eco-fascist new world order.
Or - as some other newspapers did - you could decide that the report's main take home message that the IPCC had now come round to the virtues of nuclear energy and was guardedly approving of shale gas.
How could the report lend itself to such different conclusions? Because it was written by a vast international committee and then tinkered with further by politicians in order to be all things to all men.
Problem is when you try pleasing everyone you end up pleasing nobody.
But at least there's one thing on which almost everyone ought to be able agree. This truly is the lamest report in the IPCC's history.