1) The difference between 16.9% and 19.2% of GDP is massive. At our current level of GDP, it's well over $300B. The idea that changing tax rates so that the receipts bounce around in that range has no real effect is just silly.
2) I'm happy to give the Republican congress the credit for the things they were involved in, but let's not rewrite history. The deficit trajectory reversed direction before 1995. The 1993 budget was passed with no Republican support and over screams that it would destroy the economy. To my knowledge, there was nothing particularly special about the 1995 budget in terms of deficit reduction.