That's the job of the photographer. The perfect meter reading must take account of the sensor DR limits as well as the photographers creative/technical priorities for the image. Only fairly average to low contrast scenes will not require any thinking about that.
All meter readings, no matter what technique is used or how much of the frame is considered, can only produce one single exposure value ... Simply metering for the full frame does not mean that any single exposure value would allow the entire DR to be recorded.
Lets hope though that the DR of our shiny new Full Frame models will take us a good few steps further towards that!