Compare
Two ways to integrate
The same starting state, two integrations side by side. Look at the shape of the history, then look at the file content — the second one is the surprise.
tip: refs/heads/main
tip: refs/heads/feature
One new commit with two parents. Nothing is rewritten and nothing is orphaned.
Every feature commit is copied into a new object. The history goes straight; the old boxes stay on the shelf.
The result
The final content is identical. Only the shape of the history differs: 5 commit objects on the left, 6 on the right, and 0 versus 2 commits with no card. That is the whole choice between them — not the work, but the story left behind.