In theory, Bill, you're right, but at a certain moment, I mean at the end of the Fifties, things were more complicated.
At this time, Rolex had some issues with the 6542 bezel, as you know.
At this very same time, things were on to change, and, in 1961, the international rule was to replace radium for tritium.
So, Swiss doesn't always correspond to Radium, at the end of the fifties, ealry sixties.
Did Rolex relume some Swiss dials, did they use Swiss dials to fill them with tritium?
Many things have been said and written here and there, but this is a fact that all Swiss dials are not radium.
We still have to work on this very interesting topic.
Best,
Nicolas