No-Crack Roasting proposes a thermodynamic and control theoretic framework for coffee roasting in which roast trajectories are intentionally constrained to remain within a feasible region that suppresses sustained fracture events commonly known as first crack and second crack. The paper argues that crack functions primarily as an observable proxy for latent thermochemical state progression rather than as a necessary mechanism of flavor development. Coffee roasting is modeled as a constrained trajectory optimization problem involving temperature moisture pressure structural evolution and pyrolysis product accumulation. The framework introduces observable and latent roast states state estimation methods viability constraints and kinetic models for flavor development and pyrolysis. Drawing on extensive practitioner observations across multiple coffee origins the paper develops the hypothesis that conventional crack associated roasting trajectories generate a perceptually dominant pyrolytic masking layer that obscures bean intrinsic flavor characteristics. The work presents No-Crack Roasting as a falsifiable scientific hypothesis and a control framework for future experimental validation rather than as a finalized roasting doctrine.