The thing about this discussion I'm a little confused about is what are your histograms showing? Or are you guys literally using a light meter based on an ISO and setting the camera? 'Cause once you've bumped the aperture to change the histogram you've effectively changed the rating of the scene.
For instance, Indoors, lower dynamic range: If you rate the camera at 320 and then use the histograms to set your exposure your net result is about like metering to 160 and exposing there.
If you've got film lighting you're fine. If you're the natural lower light light indie guy... well, crush the blacks. Build 16 may well smooth the transition into underexposure and effectively help speed the camera up in these situations.