fact that Claudia has a similar function in two different films by different directors seems no more than an interesting coincidence.
For Cheyenne there is (as usual by Leon) a very small scene at the end. Just before the final showdown, Cheyenne goes to the McBain farm house, to “shave”, but he – by the way, and this is the trick of Leone – washes his face twice. And to make emphasis on this, he looks into the camera. This is the final statement of Leone of the relationship of Cheyenne to water. Jill gets her big bath, and even Cheyenne get his small face washing. They are both standing on the “right side” of the water.