ELAC
"Perhaps, but at least there's no doubt about the expat Captain being the designated PIC there."
I would think that the Air China Chinese Captain signing your log book at the end of every flight may suggest otherwise.
I hate to drag out what is becoming an overly long and redundant debate, but just so it's clear for Mastema:
The Chinese carriers I'm familiar with publish a document referred to as a "mission certificate" for each planned operation. The mission certificate lists, among other things, the assigned duties for each crew-member. If you are the designated PIC you know it, and so does everybody else. If you're not, the same goes.
The signing of logbooks is more of a formality than anything else. I have frequently signed the logbooks of training and CAAC check captains who were the designated PIC's on flights I've done with them.
Regards,
ELAC