Nothing Is Overwritten — What an Inherited Notebook Needs to Be Useful

Stated up front. In May 2026 this magazine ran a piece about inheriting a father's work notebook. This is not a specific workshop. We constructed the shape exactly as it actually works, and we do not name where. What follows was built to that shape, and the contents of the notebook are invented.

The difficulty of an inherited record is not reading it. It is that you cannot tell who knew what, and when.

Suppose there is a line: "In the rainy season, back the third valve off half a turn." The worth of that line changes completely depending on who wrote it. Written by somebody who ran that machine for twenty years, it is gold. Copied out of a manual by a temp, it is something to check.

A paper notebook does not tell you which. And something worse happens — when a line is proved wrong, it gets erased.

A correction is not a deletion

You could say this is the whole of what this tool does.

/// The id of the line this one corrects, if any. A correction never deletes.
final int? supersedes;

What that actually looks like is in the log.

Father 1998: In the rainy season, back the third valve off half a turn.
             -> ran without jamming that summer
             [corrected by Son 2019: New seal kit since 2018 — the valve trick is no longer needed.]
Father 2001: Warm it fifteen minutes before the first piece, not ten.
             -> first-piece scrap dropped
Son 2019:    New seal kit since 2018 — the valve trick is no longer needed.
             -> no jams in two seasons without it
Son 2023:    Fifteen minutes still right after the motor swap.
             -> not written down

The 1998 line is still there. All that happened is that a note appeared beside it saying the seal kit changed in 2019 and it is no longer needed.

Why keep it? Because it is not a wrong line but a line that was right at the time. Backing that valve off half a turn was correct in 1998, and if you erase why that judgment was correct, the next person starts again with no grounds the next time the seal kit changes.

// A corrected line keeps its text and gains a pointer. It never
// disappears — the previous owner's reasoning stays readable.

Hiding and erasing are different

That does not mean you need to see every old line every time. So there are two screens.

The full view shows every line ever written about that machine. Corrected lines are still there, wearing their correction.

The "what still stands" view leaves the corrected lines out.

The log states that relation directly.

standing: #2 Father 2001, #3 Father 2004, #4 Son 2019, #5 Son 2021, #6 Son 2023
corrected line #1 is absent here but still present above

Line 1 is not here, and it is up there. And that is written at the bottom of the screen — "Corrected lines are hidden here, not gone."

The verification looks at both.

grep -q "back the third valve off half a turn.*\[corrected by Son 2019" captures/run.log \
  || { echo "   a corrected line lost either its text or its correction"; exit 1; }
grep -q "corrected line #1 is absent here but still present above" captures/run.log \
  || { echo "   the corrected line was not hidden from the standing view"; exit 1; }