The closest thing I'm aware of is ":earlier {N}f", which "[Goes] to older text state {N} file writes before.". So once you're somewhat happy with what you've g

The closest thing I'm aware of is ":earlier {N}f", which "[Goes] to older text state {N} file writes before.". So once you're somewhat happy with what you've got, write the file, and then continue editing, repeat, and you can revert back to any previous saved file state.