Do you believe that Reagan's first tax cut paid for itself? Did reducing the top rate from 70% to 50% cause more revenues to come into the government's coffers? Did that reduction in taxes help the economy to grow faster and did it result in higher after tax income for America's citizens?
Given the limitations of the Laffer curve that I listed in the previous message, I don't think there is enough historical data to answer those questions. Individual income tax revenues did drop sharply from 1982 to 1984 so they did not appear to increase in the short-term. Then the 1986 tax cut further reduced the top rate to 28% and changed the tax structure (reducing many deductions) so it's difficult to make any judgment about the medium-term.