a while back. Cloudy is clearly a "black key" piece, and I assume that's why it has that pentatonic sound. Charlie Davis may have heard and seen Bix play Cloudy, or something similar, and maybe it stuck in his mind for that reason that Bix was a black key man. I agree with Mr. Pletcher that the piece has none of the hallmarks of the mature Bix, which is why I thought it might have been something he played around with as a kid. I will presume to mention my own meager piano expertise here, but when I was a kid I often played around only on black keys--I liked the dreamy feel of the pentatonic scale, but as I played more and studied more and needed to move around the keyboard way faster, I tended to stick to pieces based on white keys. My point here is that for people with close to perfect pitch (in Bix's case, astoundingly perfect pitch) the keys all have different characters, and, frankly, some of us just like F sharp best of all. So the black key thing as a youthful fascination is feasible in my view.
But I defer to Mr. Pletcher, as he seems to have discussed Davis's performance in the Berman film with many who heard Bix in the flesh and lived with him closely enough to have noticed if he had ever played anything like Cloudy in their presence. Since they unanimously seem to have denied ever hearing such a thing from Bix, it sounds as though Davis either mis-remembered or is a tale-spinner. But it also may be that it's true (very hard to prove a negative), and I think it is a possibility that Cloudy or something like it may have been Bix's. But my real point is that it SOUNDS TO ME as though it could have been, and to refute that, I was hoping for a musical, not a historical, argument.
Unfortunately, I don't have the musical vocabulary to state what I mean more clearly. Let me just offer the analogy that I think, for example, Bix's Wolverine solo on Royal Garden Blues is as different from say, his Sweet Sue muted solo as Cloudy seems to be from In a Mist. Lacking better words, the later creations are more mature, more richly implying other chords, more subtle and less straightforward, but to my ears, sound like they probably came from the same mind. Sorry I can't do better! I must defer to those who actually lived with and heard Bix!