AI-free fluency (Bare mode)

A trainee London cab driver follows a satnav on every shift. Twice a month she sits across from a Knowledge examiner, who names two points; she calls the route street by street, with no map and no device. A route she half-knows comes out with a wrong turn the satnav would have hidden. After each appearance she writes down every street she got wrong and rides those streets on her moped the next morning. A classmate who drove for months on the satnav alone finds that his routes have gone.

At the examiner's desk	In a bare round
The satnav on an ordinary shift	The assistant, autocomplete and run button on a normal day
Calling the route aloud, no map	Writing the code and running it in your head
A wrong turn the satnav would have hidden	A contract misremembered at an edge
The missed streets, ridden the next morning	The miss list, drilled at the next session

Breaks down when: streets change slowly, while runtimes and libraries change versions, so a contract you drill belongs to a version. Wrong inference: "a contract learnt once holds in every runtime." An examiner also hears only the route, while an interviewer reads the code too.

In real terms: in a bare round, the everyday contracts come from memory, and you can say what your code prints without running it.

4.1 EXH-3170: a bare session and its miss list

In a practice session for ExamHall's exam page, the candidate wrote formatRemainingTime in a plain editor in 15 minutes and ran nothing until she called it done. Then she ran the kata's 8-test list (EXH-3170) and wrote one miss-list line per red test. A week later, after drilling the list, she wrote it again from a blank file (MR !3470).

4.1 EXH-3170 week-1 draft            0 of 8 pass · every test throws TypeError: n.padStart is not a function
4.1 the same draft, padStart line fixed  6 of 8 pass · red: "1 ms left shows 00:00:01", "a passed deadline shows 00:00:00"
4.1 miss list, each line run: typeof (5).padStart is "undefined" (a string method) · Math.round(0.001) = 0, Math.ceil(0.001) = 1 · spec: a passed deadline, Math.max(-1500, 0) = 0
4.1 MR !3470 week-2 draft            8 of 8 pass

All three misses were contracts or spec cases she had never had to recall, because a run used to show them at once. The second draft passed without a run in between.

4.2 Payments ledger: predict, then run

Warming up on a payments ledger, she wrote down the result she expected for four everyday calls, then ran them:

4.2 entries.push({ id: 'JE-7' }) on 2 entries  predicted the new entry got 3      miss
4.2 Math.floor(-25 / 100)                      predicted 0             got -1     miss
4.2 -25 % 100                                  predicted -25           got -25    hit
4.2 '1234'.padStart(3, '0')                    predicted '1234'        got '1234' hit

The two misses went on her list; the hits did not. Each miss line names the call, her guess and the real result, so the next session starts with those two.