This article by Bill Bischoff describes some of the many problems related to Targeted Tax Policy. http://www.smartmoney.com/personal-finance/taxes/the-road-to-tax-reform-starts-here/ The Hedghog agrees with most of the points raised.
However, the idea that tax reform can begin with a few steps is just wishful thinking. Election cycles come and go. Politicians are powerful (and weak). Special interest pleadings go on and on. The needy are perpetually needy. Whatever reform that is devised is simply undone or revised to be unrecognizable.
Without limitations on the reach of politics, welfare states eventually go out of fiscal control. The Hedge Tax was devised to force the balance of taxes and expenditures. But it was also devised to put all citizens on the tax rolls in a way that focused voter attention and ended class warfare on taxes.
It might take a near revolution to implement such a plan. When viewing the video of the Greek crisis, that day seems closer.