Peter Orszag for Bloomberg here likes the idea of flat tax deductions for some reason, but not flat taxes.
Maybe it's because such equality in deductions would increase the taxes paid by the top 25 percent of taxpayers, who already contribute the vast majority of the government's revenue. Orszag sees no reason why a person in the top marginal tax bracket should have his taxes reduced at that marginal rate by a deduction for a 401K contribution, or a mortgage interest payment, or a donation to charity. He wants the deduction to be a flat deduction for everyone, regardless of income, which sounds to me like an admission that there's something actually immoral about progressivity in the tax code.
Sounds like progress to me, the logical implication of which is that the tax rate also should be one flat rate for all.
In the meantime it remains that "tax reform" is to "progressive" as "tax increase" is to "liberal." The name has been changed to disguise the guilty.