Nic Lewis and Marcel Crok have just launched Oversensitive.org, a new website to document the responses to their GWPF report of the same name. Of particular interest is a post outlining Jonathan Gregory's claim that he had shown that the method used by Lewis underestimates climate sensitivity.
It seems that (surprise, surprise!) Gregory's case is based on the output of a climate model, although he neglects to say so. To put forward a hypothesis and to claim it as a proof is shoddy stuff, but all too predictable in the world of climate science.
Reading between the lines it looks as if Gregory has misunderstood the Lewis method and is now rather stubbornly refusing to admit that his mistake.