The irrationality comes from the fact that I end up with exactly the same text file no matter what. My edit path (directed graph of atomic edits that arrive at the new file) can go many ways to the same result, but I find myself hating one path, and liking another. Even in the "good" path results in more keystrokes during editing. When I save my changes to git or svn or whatever, the new file will be the same regardless of edit path taken to create it. But during the editing operations, I had a nagging pull to make sure the characters I changed were from the copy.