EXD.6:4.3 - Obtain only the evidence that can change the choice

First inspect subject correctness, missing claims and explicit contradictions. These can justify a repair before a reader trial. Use a reading or application probe when the live alternatives concern recoverability or receiving use and its possible results can change the choice.

Preserve the initial response before assistance. Identify what the recipient had available at each point and what the subsequent help contributed. Prior knowledge can enable reconstruction; independent correction of an absent or false instruction must be identified rather than credited to the expression.

If the same person sees both explanations, prior exposure or practice can affect the second response. Design the comparison for the conclusion sought or retain that attribution limit. A small local observation may suffice for a local repair; a general effect claim needs a design and evidence appropriate to that stronger question.

If useful observation is unavailable, retain a sufficient incumbent or make a reversible design choice with its intended gain stated as an expectation. The absence of a measured human effect does not prevent a qualified explanation from being used.