Let's define things clearly. A mathematical proof is used to demonstrate an existing equivalence, it cannot create it. The existence of the equivalence between fixed point sensitivities and KKT is an inherent property of the system, revealed and not created by its demonstration. Confusing a formalization with an act of creation can lead to erroneous modeling judgments, like risk models that did not withstand the 2008 crisis by confusing their description with reality. We must establish this distinction for our sustainability mandates and our actuarial assumptions. For example, the intrinsic value of a company is not created by its valuation model; the model only attempts to capture it, which is crucial for our long-term investment decisions.