> First, thanks to the incredible complexity of the U.S. fiscal system, it's essentially impossible for anyone to understand her incentive to work, save, or co

> First, thanks to the incredible complexity of the U.S. fiscal system, it's essentially impossible for anyone to understand her incentive to work, save, or contribute to retirement acounts absent highly advanced computer technology and software. If the article is arguing that everyone pays roughly the same taxes, that would mean we have a de facto flat tax anyway so the incentives should be clear. > Second, the U.S. fiscal system provides most households with very strong reasons to limit their labor supply and saving. That would mean unemployment would be low, given the lower labor supply. > Third, the system offers very high-income young and middle aged households as well as most older households tremendous opportunities to arbitrage the tax system by contributing to retirement accounts. If one had a crystal ball, yes. Marginal tax rates are at some the lowest in 60 years, so it is entirely possible that they will be higher at the time of retirement withdrawal. > Fourth, the patterns by age and income of marginal net tax rates on earnings, marginal net tax rates on saving, and tax-arbitrage opportunities can be summarized with one word - bizarre. Doesn't sound very objective.