A tiny change like a typo in a comment I would just edit in both the git commit --patch `e` editor and in the working tree copy. Anything bigger I'd either abort or skip and edit/test normally and then amend. My main use for `e` are not really edits to the final code but rather for splitting up changes that affect the same line.

I only had problems with errors from `e` on Windows - I'm guessing due to wrong line endings.