If the listener insists the promise did not happen at all, a reply such as “Rather, it certainly did” addresses event occurrence. But if the listener accepts fulfillment and asks only when, “It happened yesterday” provides the decisive information. The same topic demands different responses according to the live dispute.
Outstanding issueAppropriate response
Denial of occurrenceAffirm the event with suitable force
Unknown timingSpecify the time
The chief rhetorical skill is diagnosing the point at issue. Ornate or emphatic language is ineffective when it fails to answer the question actually under discussion.