Actually, someone did just create what is supposed to be a Greasemonkey script to force the English titles clientside using a remote list, but I can't get it to work:
http://userscripts.org/scripts/show/160951
This alternate script does work fine for me, but you wouldn't be able to make your own title database with it.
http://userscripts.org/scripts/show/160952
Can anyone test these and see if they work for you?
Non-cache one works for me.