Fortunately here is where the power tools come in. I
- re-merged the backed out revision, postponing conflicts;
- saved the diff away and reverted the repository;
- wrote a small awk script to massage the hunks in the diff to get a new patch;
- fired up emacs with the patch and applied each hunk after thorough review (and seldom with minor changes);
- some hunks are not ready to go in yet as they do not qualify as refactoring, these are kept for later;
- commit almost every file as a separate revision.
- it provides all necessary hunk operations such as apply, reverse, go to original, drop etc.
- I can transparently work from a remote machine via ssh, including editing, version control and the above diff operations
- peace of mind, by being rock solid and autosaving stuff.
Thanks Emacs, without you I would probably drop!