It's one of those things, no one ever is really going to know.
The other thing that leads me to believe they WEREN'T purposefully soured is simple, we have no OTHER intentionally soured styles here in America. The Berlinner Weiss is German, The other sour beers are traditionally Belgian styles. You don't hear anything necessarily at all in the entire canon of American Brewing about any purposefully soured beers. So why would we expect a virtually extinct regional style to be any different than any other American beer from that period? You would think it would have escaped out of the hollars of Kentucky in some form somewhere.
I tend to think that the Kentucky Common is really just like any other common/cream ale/(even steam beer) of that period, just a regional variant that was darker than other versions, and none of the other versions are thought of as intentionally soured.
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Revvy's one of the cool reverends. He has a Harley and a t-shirt that says on the back "If you can read this, the bitch was Raptured. - Madman
I gotta tell ya, just between us girls, that Revvy is HOT. Very tall, gorgeous grey hair and a terrific smile. He's very good looking in person, with a charismatic personality... he drives like a ****ing maniac! - YooperBrew