patch series vs. multiple files changed in a commit; storytelling history vs. literal creation history

I've read Documentation/SubmittingPatches, followed some of the discussion on this list, and looked over some of the recent commit history. I'm impressed by the strong culture of review that produces readable patches and commit messages, but I think there are some gaps in my understanding of the prevailing process here.

Most of the code I've worked on has been closed source, and the commit histories tend to reflect what I'd call the literal "creation history". Reading the Git history, my impression is that it reflects a different "storytelling" history. In some cases, that might be the same as the creation history, but in general the emphasis is on telling a coherent story of the changes to the other developers rather than communicating all the messy details of how you arrived at the order of that story. Is that right?

What are the Git project's rules of thumb for when to create a patch series vs. putting changes to multiple files in a single commit/patch?

As a patch series evolves before landing on an upstream branch, do you typically make corrections to the original series in new commits, or update the respective commits from the original series in a new series of analogous commits?