re. 09:00GMT comment --- I think you may have looked at the wrong PR. DokuCssFile->load() is part of PR#407 fixing FS#2875
There is only one file changed in the branch, FS#2879
The change is solely concerned with updating relative url values in replacements.
re. 10:28GMT comment --- I have wondered about that. I intend to discuss with other developers at next irc meeting.