I don’t quite think you got his point since they are not literally the same. 32/64 implies an accuracy of 1/64th or .01563. 0.5 implies an accuracy of 0.05 or half of the increment of measurement (0.1 in this case).

I don’t agree however that fractions are more accurate since it is arbitrary. For instance 0.5000 is much more accurate than 32/64 or 1/64.

Just factual content

This was just part of an idea I thought I’d post since it sounded fun. I replied to the other commenter with similar questions but I’m not currently DMing otherwise I would figure that out.

Oh I don’t know. I just thought it’d be a cool idea and so I posted it. If I was currently DMing then I would figure that part out. Maybe the “keys” reveal details about the BBEG like they’re all of dwarven make or a certain script. Maybe one key could only have been made by some famous smith in a certain town.