# Demonstration: The Same Change, Told Two Ways

## OBSERVE

```
$ git log --oneline
a1b2c3d fixed stuff
```

One commit, an unhelpful message, and (imagine) 15 unrelated files changed together: a bug fix,
a typo correction, and an unrelated half-finished experiment.

## HYPOTHESIS

Predict: six months from now, could you (or a teammate) confidently `git revert` just the bug
fix from this commit, leaving the other 14 files untouched?

## INSPECT

No — reverting this ONE commit reverts everything in it together, including the unrelated
typo fix and experiment, whether you want that or not.

## CHANGE

The same work, done as three separate, well-described commits instead:

```
$ git log --oneline
3f9a1c2 Fix null-pointer crash in payment retry logic
9d8e7f6 Fix typo in onboarding email template
1a2b3c4 WIP: experiment with new caching strategy (not ready)
```

## VERIFY

Now `git revert 3f9a1c2` cleanly undoes JUST the payment bug fix, with zero effect on the other
two — because each commit is one logical, independently-reversible unit of work.

## Instructor Notes

**Demo goal:** Make the practical cost of "fixed stuff" commits concrete — not a style
preference, a genuine loss of capability (precise revert, clear history, easier review).

**Approximate timing:** 8 minutes live.

**Common mistake to watch for:** treating this as a purely aesthetic preference rather than a
practical one — reinforce the concrete "can you revert just the bug fix" test.