Nikon (and others) moved to MC (Meter Coupled) Lenses – AND – allowed ⅓Stop increments of the aperture, via the camera body, not the lens.
This marketing feature did not only progress on the Aperture available: it was quoted on Filter Factors, Film Speeds; Reciprocity Factors; ‘best practice’ for Test Strips; Light Meters, etc.
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However, as one first step, I think there would be some credence drawn by aligning the time lines of when different photographic gear ‘progressed’ from ˝ Stops to ⅓ Stops.