Print sample routes, then walk them. Time typical journeys, note barriers, and photograph oddities that confuse models—locked gates, missing curb cuts, or unofficial paths. Compare results with your proximity scores, and record discrepancies systematically. These low‑tech audits recalibrate assumptions better than spreadsheets alone. Share field notes publicly so others can replicate or contest them. By grounding math in scuffed shoes and real minutes, you build credibility that spreadsheets cannot purchase and dashboards cannot simulate.
Testing should illuminate, not manipulate. A/B experiment different map annotations or proximity contours, measuring comprehension, not just clicks. Use short sessions, minimal data, and debriefs that explain purposes plainly. Avoid dark patterns, and compensate participants fairly. Publish null results alongside wins so learning compounds. When communities see careful testing aligned with their interests, they become generous collaborators, offering sharper critiques and creative suggestions that lift the entire project beyond any single release cycle or dataset.