There is some truth to that. If you accept all of the worst case scenarios of CAGW, and all of the assumptions about tipping points and catastrophes, and all of the assumptions that the Earth’s climate would not self regulate as cloud formation and other unquantified and unknown processes responded to any warming, and you assume that mankind will suddenly become stupid and stop adapting to climate, then the thermageddon that might conceivably result would not be immediately reversible.
On the other hand, maybe only tens of millions of people would die (mostly in third world countries of course) before even progressives begin to realize that decarbonizing the global economy was a really dumb idea. So if we don’t throw the bums out in 2012, there are always later elections.
The central problem is that we know for a certainty that progressives screw up every economy they get their hands on. And the chances of thermageddon are probably about the same as a massive asteroid hit. Not that anybody on the planet is actually capable of computing the actual risk of CAGW
So on the whole, I think I will vote for not engaging in the willful and certain destruction of the economy, and take the miniscule risk that we will fry before we get smashed by an asteroid.