Bovi and I were discussing this with makanyane in the TWC thread that finally led to this breakthrough, and her theory is it's related to certain climates, specifically:
Does RTW (and thus EB1) have the same file, and does it include some climates that have winter and others that don't? Why yes, yes it does. Again, that doesn't mean there's a definitive link. But am I changing my directory to C:\EB1? Why yes, yes I am.
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