What the hell is up with that, anyway? Whose bright idea was it to say, “Hey, you hear that note you’re playing there? It’s a C! Well, not really. But we’ll call it a C. We also spell the word “word” as “umpb” because we felt like backing up the entire alphabet by two letters. Still pronounced the same, though! Why is your eyelid twitching like that?”
Seriously. Who the hell’s bright idea was that? If the music says C, I want to hear a flippin C.
However, at least it explains why Scott Joplin wrote seven billion pieces of music in Bb. It never made sense to me, especially on an instrument that cares so little about key; even for the white-keys-are-C-Major piano, there really is very little difference in difficulty between different key signatures on a piano. (In fact, C Major is probably one of the less hand-friendly ones since you are scooted all the way down onto the bottom half of the keyboard. Most of the hand-friendlier key signatures have a black-white-black or white-black-white home chord at their base. I’ll take EbM or Fm over CM any day.) I pretty much compose in any key that I start playing in, which makes my choices of key signature somewhat random — yet Joplin could beeline his way to and from Bb like a homing pigeon.
And according to the biography that I read, he was hand in glove with brass bands. He probably felt at home in that key and was pleased to make his work easier to adapt for his colleagues in brass ensembles.
It actually makes one consider the structure of his pieces somewhat differently, almost as if the Bb themes in his pieces were sort of meant to be accompanied by a brass band, and the areas where he wandered off to other keys were supposed to be almost solo piano bits — almost as if the pieces have a sort of concerto form where the piano can be backed up by a brass “orchestra” in the Bb themes, and then wander off on its own. It would be interesting and fun to see if arrangements couldn’t be done with this idea in mind.
Anyhow, this “transposing” crap is nuts. See a C, play a C, damn it.