HCD.24:5 - Archetypal Grounding

HCD.24:5.1 - A correct ratio and an unsupported cause

This constructed exercise uses HCD.22’s personal diagnostic case. Pressure is already measured at 400 ± 4 kPa; flow is 99.5 ± 1 m³/h and power 22.3 ± 0.2 kW, compared with the supplied baseline of 100 m³/h, 400 kPa and 20 kW. The task’s qualified account states what the constant-efficiency resistance explanation would predict. No further worthwhile observation is obtainable within the case.

Work A correctly computes the approximate increase in the power-to-flow indicator, then recommends correcting increased resistance. Work B preserves the indicator change but says the unchanged pressure fails to support that simple explanation under its assumptions. The review criterion is whether the recommendation is warranted by the supplied evidence, rather than which work sounds more decisive.

The reviewer first prefers A because it offers an action. Comparing the observation-to-recommendation parts reveals the missing inferential step. Calibration asks the reviewer to identify the expected pressure under A’s account and compare it with the measured pressure. The reviewer then returns a specific comment: retain the arithmetic, withdraw the resistance-specific remedy and state the remaining explanation question and present limit.

The author accepts the mismatch but initially adds “take another pressure reading.” The reviewer points to the already obtained reading and exhausted useful-observation condition. The author replaces that instruction with a bounded conclusion and a return for a qualified alternative explanation if the receiving work requires one. A prepared mentor resolves any dispute about the subject model; peers do not authorize a real plant intervention.

Both sides now have a learning result to inspect. The author revised the inference; the reviewer corrected a preference for actionable-sounding text and applied the criterion. The initial and helped judgements remain distinct. The contrasting case in §5.3 supplies a supported action recommendation. These exchanges require their own preparation, time and qualified help in HCD.28’s product cost.

HCD.24:5.2 - When comparison cannot be made

Two internal teams offer review material. One can disclose a full assumption-to-result fragment; the other can disclose only a recommendation. Ranking the recommendations would ask peers to infer the absent ground. The organiser obtains a permitted constructed counterpart with the same relevant relation, or limits the second review to clarity. The learner can still practise the first criterion on suitable material, but the closed project has not received that review.

HCD.24:5.3 - Retaining a warranted recommendation

A separate constructed instrument-check exercise supplies two reference values, 0 and 100 units, with a permitted error of ±1 unit. Repeated readings are 6 and 6 at the first reference and 106 and 106 at the second. The training procedure permits referral to a qualified calibration service after repeated checks outside tolerance. It does not require the learner to identify the failed component before making that referral, and it does not authorize the learner to adjust the instrument or declare it fit for return.

The author recommends the permitted referral and a new check before the instrument returns to use. The peer objects: “You have not distinguished a sensor fault from an electronics fault; withdraw the recommendation until you can.” The author accepts that the physical cause remains unknown but rejects the requested withdrawal. Both pairs of readings are six units above their references, outside the stated tolerance. The recommendation invokes the supplied referral criterion; it does not claim a component diagnosis or prescribe an adjustment.

A prepared instructor receives the disputed recommendation, readings and procedure. The narrow question is whether the missing component diagnosis defeats this next action. The instructor confirms that the referral criterion is met and explains the separate authority needed for adjustment and return. Both learners receive that resolution. The author retains the recommendation and its bounded ground. The reviewer withdraws the cause-demanding objection and replaces it with a supported judgement: the referral follows, while the cause and fitness after service remain to be established. The correction changes the reviewer’s own criterion application instead of merely marking the author’s comment resolved.

After the initial reading and comments, this example reserves a ten-minute shared window: three minutes for the author’s ground, four with the prepared instructor, and three for the corrected review and author’s response. The resolution therefore adds twenty learner-minutes and four instructor-minutes; initial preparation and review are counted separately. If the instructor must first reconstruct the procedure or the dispute remains unresolved, that larger requirement returns to the arrangement. A later independent case, if required, tests the reviewer’s new judgement; the helped correction alone does not establish it.