Unsubscribe enforcement: controlled checks and usability study protocol

Observed controlled-test findings — 16 September 2026

Three selected suppression checks passed; recipient discoverability and usability remain unmeasured.

No recipient participated in these checks. Completion time, discoverability, assistive technology, every opt-out path, live delivery and legal compliance were not tested.

1. TestUnsubscribeSurvivesContactDeletion accepted a one-click POST for a stored token with no corresponding contact row and established a suppression lookup for that email. The fixture does not perform a contact deletion transaction.
2. TestSuppressionAndFailedLookup delivered no fake SMTP message for the unsubscribed fixture and returned zero reenrollments. A missing suppression archive table caused the lookup to return an error; the test does not by itself cover every send-error recovery path.
3. TestAtomicImportAndOwnerSuppression rejected a mixed valid/invalid bulk import without partial insertion, deduplicated the valid fixture, shared suppression across one owner’s workspaces, prevented cross-workspace modification and kept a separate owner isolated.

Define the decision

A limited controlled software investigation was completed on 16 September 2026 against implementation e77303e. Its observations are reported below. The broader field-study protocol remains unperformed; software fixtures are not campaign or participant data. The decision is: Can a recipient express an opt-out and does the system prevent the next eligible send? The observation unit is one controlled recipient journey. Define the population and owner before collecting records; do not substitute an available convenience dataset without documenting the change.

Work through the procedure

1. Define reply-based, body-link and header-based paths separately. Prepare an owned address and a queued test sequence.
2. Observe discoverability without coaching, then verify suppression state and attempted later enrollment. Test supported paths only.
3. Before collection, write the primary outcome, observation window, exclusion rules and stopping conditions. Preserve excluded observations with a reason rather than quietly removing them.
4. Pilot the procedure with fictional or owned test data, resolve ambiguous fields, and freeze a dated protocol version before the main run.

Worked example

The following is a synthetic example for this procedure, not a customer result or performance benchmark.

recipient chooses body link; confirmation appears; suppression recorded; subsequent controlled enrollment/send check must remain blocked
Suggested record fields: observation_id, condition, evidence_reference, outcome, exclusion_reason, reviewer, protocol_version
Status: illustrative record only; this example is not an observed result. See the separate controlled findings above.

Read the result

Report user completion and operational enforcement separately. A friendly confirmation page cannot establish that suppression worked. Keep the numerator, denominator and missing evidence visible. If the available observations cannot answer the registered question, report that limitation rather than selecting a more favorable metric after collection.

Collect the evidence

Observation unit: recipient-journey.

Owned recipients, supported opt-out paths and an isolated queued sequence.

Test discoverability separately from enforcement; never recontact a real opted-out person.

Analysis: User completion and subsequent sending prevention as separate outcomes.

Download the JSON collection template under Source references. Set an owner, eligibility rules, outcome definition, observation window and sample justification before collecting records. Templates contain no participant data or results; keep original private records outside the public website.

Check before moving on

1. Name the person responsible for collection and review.
2. Check that the evidence can be inspected without exposing private messages or credentials.
3. Record deviations from the protocol and analyze their possible effect.
4. Retain a dated, redacted evidence worksheet with the final interpretation.

Limits and next action

This is a usability and behavior protocol, not a legal compliance certification. Never test by recontacting real people who opted out. Publish results only after the evidence, method and limitations have been reviewed. This protocol provides no benchmark, expected lift or completed field-study claim.

Source: Method or workflow reference