The IPCC Trick 5: What Lindzen, Monckton and Spencer Missed

This thread on the IPCC trick argues that climate sensitivity as the global warming by doubled CO2, is less than 0.3 C. There are other skeptics including Lindzen, Monckton and Spencer who also argue that climate sensitivity is smaller than the 3 C of IPCC.

But Lindzen, Monckton and Spencer seem to have missed the argument of this thread:

• Lindzen presents a big radiative sensitivity moderated to about 0.5 C by negative thermodynamic feedback.
• Monckton swallows the IPCC no-feedback value of 1 C and uses negative thermodynamic feedback to bring it down to about 0.7 C.
• Spencer finds a value of about 0.5 C, or less, from measurements of variations of surface temperature and outgoing longwave radiation, which in spirit is close to that of this thread.

It would be interesting to hear what Lindzen, Monckton and Spencer say about my argument.

None of them seems to question backradiation, which is the gist of my argument. If it can be shown that climate sensitivity is less than 0.3 C, then AGW is dead.