I think the D600 could use another stop of ISO range
If the extra ISO step isn't natively supported by the sensor, i.e., the camera is doing the multiplication, you're just as well if not better off doing the extra push in PP, where you have nicer tools to clean up the ensuing mess, err... I mean, results.
Good call, and a simple solution which I had not considered. And I agree the results are likely to be interesting.
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