Good job finding the dialect reference.  Often straight-ahead white music was issued on Race records, even on Black Swan Records.  I figured he sang it straight, but I've never heard one of his Paramount or Vocalion "race" disks.  Haven't seen one either, they are very uncommon.  Now I'm really curious.  I'll look on JSTOR.  I just got access, several months after being approved.   (spin me / revolutions)