Richard,
There is no conspiracy. The IPCC tries to construct a plausible scientific story that supports the idea of anthropogenic warming, and in part this requires the diminishment of the role of natural variations. The thing that truly puzzles me, is why the IPPC believes it is so important to build such a story, when in fact it is irrelevant. CO2 is a GHE and therefore rising emission levels need to be addressed; the scientific questions will be resolved by building a better understanding of natural variability.
