Exploratory Technical Note: EM-style Optimization for Differentiable Renderers

This technical note outlines a conceptual EM-style alternating optimization framework for task-driven differentiable renderer tuning. It proposes a theoretically plausible algorithm and discusses open issues such as training stability and long-range gradient propagation, without formal proof or experimental validation. The document serves as an archival record of a partially developed idea from an unfinished PhD-era project.