Alright, just for fun, now that I'm thinking about it, I'll try to come up with a few more arguments that the Southfarthing produced Straight Brightleaf:
- Tolkien smoked a Straight VA (somebody here recently posted an image of his receipt for a transaction the year before he died. It was for 1 lb. of Capstan Blue). Tolkien more than once said that he saw himself as a Hobbit in his preferred lifestyle, clothing style, and food tastes. So the default assumption is that he imagined Hobbits smoking brightleaf.
- Tolkien emphasizes repeatedly that Hobbits are "simple folk." Their food is plain and hearty, and they stereotypically eschew the exotic. In pipe culture, this would correspond to simple VAs, I think, as distinct from Latakia, Orientals, etc.
- In "Concerning Pipe Weed" (quoted in my signature), no mention is made of the kind of processes which produce Latakia and DFK, nor of any other specializing process. An argument from silence is worth only so much, granted, but we might have expected him to mention these things considering his tendency to geek out on details.
- To those who read Tolkien in terms of his own, occidental conservatism, and who are not overly concerned about political correctness, it seems that The Shire -- considering its ways and its westward location -- channels something like England, and that everything East of that is (to a Hobbit's mind) rather more exotic. Those Eastern lands would correspond to the places where most other varieties of leaf are produced.
Now I'll grant that most of these considerations work equally well for burley. I can see that.
But there are still reasons to lean towards brightleaf vs. burley on this question; namely,
(a) the first reason listed above, that Tolkien's own preferences leave us with a brightleaf default, and
(b) if The Shire in some sense channels England, then we must not forget England's relationship to the Virginia colony and the resulting predominance of Virginia tobaccos coming into English ports.
...Ok I'll berth this ship now...