One Fist Too Many
It feels like the “Harmonica” character was inserted into Once Upon a Time in the West after-the-fact. He’s sure unnecessary. He makes the movie longer than it need be, attracts time away from the main plot for no good or interesting reason, and generally clutters the situation. I think he wasn’t supposed to be there; that Cheyenne was the only male protagonist, and that half of Cheyenne was split away to form “Harmonica” (who, note, is an Indian — yet the other guy is named Cheyenne).
Assuming this is the case — well, why? I’ve an idea it has to do with Ennio Morricone. You see, by this point he was no longer writing the music at the last moment. I understand that, after the success of The Good, The Bad, and The Ugly, where he wrote a number of themes beforehand, he began to work more closely with Leone, working out the music before the movie was set, such that Leone would have something to guide him, conceptually.
From how he’s used, it feels like “Harmonica” was an experiment in tying the music more closely to the material. In other words, he’s an artistic gimmick. He plays harmonica (poorly), which gives an excuse for a harmonica theme to dominate the soundtrack, blurring lines that really don’t need to be blurred.
I feel that’s enough Leone for me, for now.