Wow..! Who knew..? Now you've advised of this, I did find this in the manual, but without knowing it was possible, unless one read the manual cover to cover, you could well miss this info. It qualifies as a Rumsfeld. An 'unknown, unknown', in my view. Unless the dealer advised about it..? Mine obviously didn't.
As it was, although I found out how to extract the key from the fob, and I found the recess under the driver side door handle, I was unable to actually achieve the opening of that part of the handle, no matter what I did, so it would still have me stranded by the roadside, if the battery/fob failed on a dark night. Has anyone else managed to actually open their locked door in this manner. It is quite an important feature really. I imagine, as there is definitely no key slot in the car when it has the Start/Stop button, that once in via the key - if you can get in, that is - the button would then work and start the engine..?
PS. My door handles are in polished stainless steel, not the car colour paint. Should that matter..? I was concerned about the force apparently needed and the risk of scratching the handle or door.