of what happened back then.
There are just too many pretty substancial 'key' events in which we seem to see changes reflected in dials not to draw some conclusions from it. Whether they are the right ones I'm sure is subject to debate for some time to come, and I'm sure categoric evidence from irrefutable sources may never be found to substanciate. You never know I keep finding all sorts.
The bit I find interesting in all of this, is that changes to service centre or workshop instructions have not surfaced as yet as to the change in dial materials and dial handling procedures...............radium was tightly controlled following on from the 1920 dial painters scare......yet tritium wasn't seen as dangerous. We see (as yet) no changes in handling procedures, disposal requirements, storage, emergency treatment if exposed to a tritium substance etc.
All very strange
regards
John