I would whole heartily agree with the above evaluation of this rose. Its beauty is indeed ethereal and as fine as any of the OGRs. That is the important point. However, I might pedantically quibble with the term 'spiral' for its petal formation. I think of spiral as the form of the typical modern hybrid tea. La Duchesse, like most OGR's, has an imbricated or kaleidoscope pattern of petals.
This is my favorite rose of all time. The delicacy of the petals cannot be described. Pale pink color and spiral form with a button eye are ethereal. Strong rose fragrance. Plentiful bloom. Beautiful leaves and color. Disease resistance.