[Cthulhu_]

Same, but at the same time the existing workflow is a bit more clumsy / these commands are a bit more ergonomic.

Fixup was already possible through `git commit --fixup`, and before that through `git rebase -i`; reword also through `git rebase -i`. I suppose the developers got enough feedback that editing a file to decide what to do with each commit was a bit frustrating for some users.

It's a higher level command on existing functionality I suppose.