One more time for those having trouble following...
Neither you, nor the TPC, can state with certainty that tax revenues will fall following a reduction in tax rates. As history shows us, sometimes revenues actually increase. But even if you don't buy the Laffer Curve, you CANNOT state with certainty which way revenues will head following a change in rates.
Therefore, there is no way to know exactly which loopholes would need to be eliminated in to make up for lost revenue...because revenue may go up, down or it may remain the same. It really depends on what happens to the overall economy.
For what it's worth, I think ALL loopholes should be eliminated. The tax code should not be used by politicians to pick winners and losers in our economy.