Beyond Snap Ratio: Reproducible Force–Travel Measurement and Exploratory Perceptual Correlates of Weight and Collapse Sharpness in Electrocapacitive Domes

Topre-compatible electrocapacitive elastomer domes are commonly described by one nominal force, yet their force-travel curves contain mechanically distinct stages that a single click or snap ratio cannot encode. This preprint consolidates a reproducible measurement framework and reports an exploratory study relating force-curve descriptors to the sole author's repeated panel-relative self-ratings of perceived weight and collapse sharpness. The objective evidence is the published Force Curve Bench fc-3.4 release: 184 retained semantic run bindings representing 180 unique acquisitions, 76 semantic records, 75 independent measurement cohorts, 68 release-eligible dome baselines, and eight part assemblies. The subjective pilot used the same 25 individual physical dome specimens as their linked objective records in three fixed-order sessions. Across 25 three-session dome means, perceived weight was most strongly rank-associated with collapse force (Spearman rho = 0.951745; 95% BCa interval 0.871075 to 0.989916), and tactility sharpness was most strongly rank-associated with force Drop (rho = 0.930200; 95% BCa interval 0.824172 to 0.979760). The resulting Weight Index and Tactility Index are single-input fleet-percentile presentation coordinates: Weight Index uses only full-precision collapse force and Tactility Index uses only full-precision force Drop. Pearson and Spearman coefficients are association evidence, not calculation weights. Press work to force-wall ranked sixth for perceived weight (Spearman rho = 0.817381) and remains a separate, assembly-endpoint-dependent full-stroke effort descriptor. Preprint 2.1 is an editorial clarification; it changes no measurements, statistical estimates, figures, index inputs, reference-fleet values, or calculations. The perceptual findings remain exploratory, single-rater, post-hoc, and in-sample; they do not establish causation, population validity, inter-rater validity, independent metric contributions, or prediction for unseen users, assemblies, or domes. The author also publishes project work as BuddyOG. Correspondence: https://unrealkeyboards.com/pages/contact