The taskforce's report last year recommended a series of policy changes to lift productivity in an attempt to lift New Zealand's living standards to those of Australia's by 2025.
They were widely criticised as radical and politically impossible to implement because they would have meant reversing National's election promises.
The recommendations included:
* Cutting government spending from 36% of GDP to 29% of GDP within three years;
* Limitations on some universal benefits including interest-free student loans and subsidies for early childhood care education; and
* Lifting the age of entitlement for superannuation.
Today in a column in The Dominion Post, Dr Brash said his prescription for economic growth would mean that the top tax rate could be reduced to 20% without the need to lift GST or impose new property taxes.
Dr Brash said the Government's goal of matching Australia is "totally unrealistic if we continue on our present mediocre policy track".
Next week Prime Minister John Key is due to outline the Government's thinking on economic policy and tax reform.
Dr Brash hoped Mr Key's speech would signal a start of serious reforms that he felt New Zealand desperately needed.
When Dr Brash's report was released last year, Mr Key said he was not in favour of the recommendations and said National would not break its election promises.
