Doug, I appreciate all of your efforts to elucidate and educate, but I'll have to disagree with your speculations about the optimum sequencing of the Step 4 Rinse, and I won't choose to experiment with it. The point of the Step 4 Rinse is exactly that: a final finishing rinse that reaches deeply into the groove to remove any remaining residue. There is no value to using it after the enzyme step but before the Step 2 surfactant cleaning step because of all the materials in any of the various surfactant cleaning fluids. As witnessed by all of our shared experiences with purer and purer water rinses, the Ultra-pure rinse eliminates residues better than plain distilled water. From my listening experiences with it, and from what Lloyd says he's doing with the formulation, the Step 4 Rinse moves us another step further ahead.
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