This is all very interesting; however, I do not see any noticeable difference in the Brown lettering captions of my three Ford
cards.
The Brown captions were printed in the initial ink printing phase (of the 6-color process) in the printing of T206's. There are
many T206 proofs that confirm this fact. Therefore, I don't expect any significant differences in the printing of the captions.
Regarding the main subject of this thread, the cigarette packaging (cutting, folding, assembling the packs and the cigarette
stuffing) was done by machinery at the "modernized" Factory's [such as the Kimball plant (#649). in Rochester, NY].
But, it's my impression that the the T-card insertion was done by the employees (usually, low paid women or teenage youth).
Inserting two cards (one on each side of the slide) in the pack was a very quick and simple process.
TED Z