Methodological Critique of Two Foundational Assumptions in Spin Experiments and Their Correction within the $\eta$-Field Geometry (CRVD model)

We first analyze the empirical failure of the idealized 360-degree magnetic-field symmetry requirement in real SG devices, arguing that these deviations introduce unavoidable systematic biases in observed angular distributions. Second, we demonstrate the inadequacy of the uniform-field assumption when considering the topological nature of spin coupling within the proposed $\eta$-field geometry.