Comments on Gary Johns "Convoy a revolt of working people" 18/08/2011, http://www.theaustralian.com.au/national-affairs/commentary/convoy-a-revolt-of-working-people/story-e6frgd0x-1226116943715
While what Johns argues may seem reasonable, the same line of argument could/would put the costs of no action on carbon equally large, or they might be even higher.
There are many variables, factors and scenarios that are very difficult to model, as most modellers or people close to modelling works are aware. This may be a double edged sword, and could be used either in favour of the Treasury modelling or against it.
The real issues are whether actions should be taken to mitigate emissions of carbon dioxide, and if the answer is positive, how actions should be taken.