>>3738296I decided to test this for myself to see what the truth is. It was actually sort of surprising.
I shot the blinds next to my desk since they have easily discernible detail in the highlights and have a somewhat muted range of subject brightness.
I used an X100s and shot everything manually. The baseline exposure was at Base ISO (200), 1/8s and f/5.6. I exposed up until the highlights were all but blown.