Shub Niggurath has been looking at the nitty-gritty of the IPCC's renewables report and, in AGW parlance, "it's worse than we thought".
...the situation is analogous to a biological experiment where some of the control cases also appear in the study group or the use of a new experimental methodology where a fraction of the target subjects are themselves used in the training set. An even more accurate analogy would be like attempting to compare two clinical studies: the first one, where a small number of patients with good outcomes are selected and the study examines patient records retrospectively to see that such patients received quality healthcare at substantial healthcare costs, and a second prospective study which aims to attain the same for all included patients, with the exact same good outcomes operating as constraints. Healthcare costs (akin to CO2) in the second study would necessarily be high! The result is circularity of inference, and the root of the problem lies in the cross-inheritance of input parameters between scenarios of fundamentally opposite types.