Les McLean said "When comparing negatives look at the detail in the shadow areas and choose the negative that clearly shows detail, my prediction is that it will be the neg given -1 stop exposure from the metered reading, placing the shadow on Zone VI."
Les, I don't think that your calculations are correct. My indications are that -1 stop exposure from the metered reading would be to place the shadow on Zone IV. The metered reading would be Zone V placement. +1 stop exposure would be Zone VI placement.
Furthermore I have found that a shadow placement Zone V and higher would seem to shove the highlight detail (in a scene comprised of a normal luminescent range of seven stops) onto the shoulder of the film curve and lead to limited highlight separation at best and blocked highlights at worst depending on the film used, of course.