The world-grounded hardness of a single sub-check. Difficulty is a
measurement, not a tag — the logistics difficulty IS the route, the
appraisal difficulty IS the lot's ambiguity. The estimator reads it to
weight the evidence: a trivial success and a formidable failure are both
unsurprising, so they barely move the estimate (desirable difficulty
enforced by the math, not a rule).
The world-grounded hardness of a single sub-check. Difficulty is a measurement, not a tag — the logistics difficulty IS the route, the appraisal difficulty IS the lot's ambiguity. The estimator reads it to weight the evidence: a trivial success and a formidable failure are both unsurprising, so they barely move the estimate (desirable difficulty enforced by the math, not a rule).