Yeah, he emphasizes that point several times over, here's one of those quotes:
http://roushpipecompany.cmail1.com/t/ViewEmail/j/FC1AD35BEF07A7FC/A9024C92F01F7963C67FD2F38AC4859C
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Very similar to how when Dunhill baccy production shifted from Murray's to Orlik and the painted lids continued to be used for packaging the Denmark-made stuff and one has to look at the ridges on the tin bottom and the cointwist top type to try and differentiate the stuff from that transition period, as detailed here by Larry Roush:"The third packaging parameter helpful in dating your tin is the type of container used to hold the tobacco. This is a particularly vexatious subject, with fragmentary and often contradictory evidence. Moreover at the end of the day since much of our ability to date a tin by type of container is in turn based on other indicators, it is far from clear how valuable this factor is on a stand-alone basis. Certainly too little information has been found to prepare a definitive and comprehensive timeline of the evolution of container type for each Sobranie blend..."
http://roushpipecompany.cmail1.com/t/ViewEmail/j/FC1AD35BEF07A7FC/A9024C92F01F7963C67FD2F38AC4859C
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