Thank you for the detailed reply. "Classroom examples of robustness problems in geometric computations" is great; I look forward to doing a deep read there. Yo

Thank you for the detailed reply. "Classroom examples of robustness problems in geometric computations" is great; I look forward to doing a deep read there. Your reference, "The Nature and Meaning of Perturbations in Geometric Computing" itself refers to "On degeneracy in geometric computations" (https://dl.acm.org/doi/10.5555/314464.314474 https://dl.acm.org/doi/10.5555/314464.314474) which I think points to a less tame reality where the answer to my question (continuity claims about CG outputs) is "it depends on the CG problem".