Teaching while you ask

Take any teach-back line on your sheet and read it aloud to someone who does not do data work. Any word that makes them say "sorry, what do you mean?" is a jargon cost, and session 3's bench prices it exactly: the question takes five minutes instead of three, because you have to explain, and it costs a point of trust, because she is a little less sure you understand her shop. The line was meant to earn trust. With one wrong word it spends it.

The usual offenders, with the plain word that replaces each. Pipeline: the steps a number goes through from the till to the report. Extract: the file we pull out of the system. Schema: the list of columns and what each one means. Latency: how old the number is by the time you see it. Granularity: per outlet, per product, or per sale, whichever is the smallest thing we count. Join: matching two files on something they share, like a product code. Warehouse: the one place all the copies are kept. SLA: the promise about when it arrives. None of the plain versions is longer than a breath, and every one of them is a thing she already knows exists.

The test is not "would a smart person understand this". Adeline is a smart person. The test is whether the word is one she uses at work, and the honest way to find out is her face, which is why the reading is done aloud and never on paper.

Douglas Hubbard's definition of measurement, a quantitatively expressed reduction of uncertainty based on one or more observations, is itself a plain sentence. It contains no term of art. It is the most-quoted line in a book about measuring the things people say cannot be measured, and a finance director can check it against her own experience without a glossary. Precision and plainness are not in tension; the words that sound precise to an analyst are usually just familiar.

There is a professional reason plain is the norm and not a courtesy. The person paying for the work has to be able to check it. A teach-back line she cannot decode is a claim she cannot test, and a claim she cannot test is one she either accepts on faith or quietly ignores. Both are bad for you: the first because faith runs out on the first wrong number, the second because you have spent a sentence and taught nothing. Plain words are how a data person makes their reasoning inspectable by the person who has to sign it off.

Look at the five false beliefs the bench can record on the fast run, because each one is a concept that was never explained. "Needs a daily refresh" attaches to freshness. "Stock levels come from the POS" attaches to typed versus recorded. "Product-level detail for the area managers" attaches to the smallest thing you count. "A dashboard is the deliverable" attaches to tool versus outcome. "Everyone reads it on a laptop" attaches to the device deciding the design. Pick the belief most likely to form in this meeting with this person, and the concept behind it is your one.

For Harbourline there are two honest candidates. Freshness is a cost, weekly is a choice, because "you'd want this daily, right?" is the belief waiting to happen the moment anyone says the report is late, and it is the costliest habit in the bank once built. Or typed versus recorded, because she assumes stock is in the POS, it is in a Friday spreadsheet with three versions, and every stock number in the build inherits that. Either is right. Choose one, not both; two concepts in ninety seconds each is a lecture with an interval.

Three sentences, in a fixed order: what it is, why it costs, what it means for her Monday. Written in full for the freshness concept, as it would be said after "if the numbers arrived a day earlier, what would you do differently?" and her answer of "honestly, nothing":

What it is. "How often a number is remade is a choice we make, not something the computer decides; the report can be rebuilt every day, every week, or every month, and the number is only as fresh as the last rebuild." Why it costs. "Every rebuild is an export, a check that nothing broke, and a person to do the checking, so a daily number is five times the work of a weekly one and five times the chances of a wrong number slipping through." Her Monday. "Your reorder is due Tuesday noon and the area managers decide once a week, so a weekly number that is right on Monday morning is the correct one, and I would rather spend the saved time making it trustworthy than making it daily."

Ninety seconds, then back to the next question. The tell that it worked is that she uses the word "weekly" as a choice later in the meeting, rather than as an apology.

The regional GM asks Adeline on Tuesday what the data person said. If the one concept landed, she can say something like "the report is weekly on purpose; daily would cost five times the work and nobody decides daily." That sentence is the whole test: it is hers, it is short, it carries the reason, and it would survive a sceptical follow-up. If instead she says "they talked about refresh rates", the concept was heard and not learned.

Write the sentence you hope she says before the meeting. It forces the ninety seconds to be built backwards from a line a non-data person could carry, and it is the cheapest rehearsal there is. It also tells you something about the choice itself: if you cannot write a one-line version a GM would repeat, you have picked an idea that matters to you and not to her.

Failing, before "who can log in to the POS back office and pull an export?": "Access provisioning is typically the critical-path dependency on data projects because credential ownership sits with IT, and if the admin account is a single point of failure we would want to get a service account issued before any ETL is scoped." True, and it fails all three tests at once: four words she would ask about, two claims joined into one, and a second sentence hiding inside the first.

Passing, same question: "Access is the first blocker on most data projects, so I ask early and I ask by name." Plain, because every word is one she uses; true, because it is a real principle of how these projects fail; one sentence, so she is answering again within three seconds. The failing version would have earned a nod. The passing version earned the name Kenneth, and later, once trust had been built, the fact that he is leaving in January.

There is only one proof that a line taught something, and it is a follow-up question from her. "So if we went daily, who would do the checking?" means freshness landed as a cost. "Wait, so the stock file is not from the till?" means typed versus recorded landed. A nod proves nothing, and a polite "makes sense" proves slightly less than nothing, because it closes the topic. Silence after a teach-back line is a reason to ask your next question, not to add a sentence.

On the bench this is the mechanism, not a metaphor. Every open question earns a point of trust, and the sensitive facts on her sheet sit behind trust gates she will not cross unprompted. The teach-back line is where that point is earned: she answers the next question more fully because the last one came with a reason. A lecture spends minutes and earns nothing, which is the same arithmetic as the jargon opener in session 3 with a friendlier face.