> And when I have to work with them, I really would prefer if git had something like `git save`. Which in the backend kept doing something like `git commit -a --amend`.

This works fine, but it encourages squashing all your changes into a single commit, rater than providing you the opportunity to build a series of commits.

Instead of `git commit -a` I have gotten into the habit of `git add -p` followed by `git commit` and breaking up my current WIP changes into themed-commits. Then later, I perform an interactive rebase and clean up my series (reorder, squash, reword, edit, etc.).

I think, as you and others in this thread describe, the pain is that forming these lightweight commits is cognitively expensive -- but like all things, with experience and practice it becomes nothing at all.