Commenters on the Rougier thread have been pointing to another very interesting discussion paper by the same author. In essence it's a call for the scientific establishment to move away from their current focus on massive and progressively more detailed climate models. The alternative proposed is simpler models, which can be run more often hence helping policymakers to get a handle on the total uncertainties.
This quote in particular was relevant to recent discussions of trust and the IPCC:
The IPCC reports are valuable sources of information, but no one owns the judgements in them. Only a very naıve risk manager would take the IPCC assessment reports as their expert, rather than consulting a climate scientist, who had read the reports, and also knew about the culture of climate science, and about the IPCC process. This is not to denigrate the IPCC, but simply to be appropriately realistic about its sociological and political complexities, in the face of the very practical needs of the risk manager.