Dude, that is awesome. I was just considering doing something like that myself, but with my rather limited skills it would have been a huge (if not impossible) project. Unfortunately I found a slight problem with uninformative error:
$> patch < class-document.php.patch
patching file class-document.php
Hunk #1 FAILED at 136.
Hunk #2 FAILED at 159.
2 out of 2 hunks FAILED — saving rejects to file class-document.php.rej
Any chance you could help out with this? I’m trying to run this from the unix terminal where I have my WP site hosted, but patch should work there…