Harvey,
It's a tough question, and one I've wondered about as well. Since it's presently impossible to precisely date most individual Graphophones, all we can do estimate. A little over a year ago I wrote an article for
The Antique Phonograph in which I attempted to date the variations of the AH Disc Graphophone. I thought that with a machine as common as the AH, and with period trade journals such as
The Music Trades and
The Columbia Record to help me, the answers would become obvious. Well, Columbia didn't publicize changes within models (probably to help clear older stock) so my dates of changes within the AH consist of ranges varying from ⅔ months to 6/8 months.
New models were, of course, quickly publicized, so for the 1900 Paris decal, study could be made of, say, the AA Graphophone introduced in 1901. Are there any early examples of the AA which lack that decal? Just an example...
I don't recall seeing a 1900 Paris on the backsides of late AGs, but that would be helpful because we have tighter dating ability with models like that. Plus, there's the article you mentioned which dates the banner decals. Using the banner decal as a reference and obtaining a large enough sample might help - but possibly only for that particular model. In other words, the AA cylinder Graphophone (as an example) might have been supplied with the Paris 1900 decal months before the AK Disc Graphophone was.
The same procedure could be used to narrow the introduction date of the St. Louis 1904 decal, but by that time the banner decals were undergoing only occasional changes, so model introduction dates would be about all there would be to work with.
I think someone should do research on this!
George P.