The blog Movies, Silently addressed recently one of those questions you never realize you always wondered about until after you hear it asked: in silent movies, who was the villain who was always tying women to train tracks? Basically, who was Snidely Whiplash a parody of? The answer’s surprising and I don’t wish to spoil it, so I’ll not say.
In another article on the same topic, Movies, Silently points out a curious phenomenon: the “heroine tied to the railroad track” gimmick is much more evident in parody — Mack Sennett films particularly, or in homages or tributes or just jokes about how they used to do things — than in the original record. (Admittedly there’s a problem studying the original record in that so much of it has been lost.) That is, the heroine gets tied to the railroad track because people think they’re riffing on the cliche of heroines getting tied to the railroad track, when the actual source is a lot less … well, visible, at least.
There seems to me a conceptual parallel in something that sounds unrelated: impersonations of Elvis Presley and (since Elvis has faded some, at least in my social circles) William Shatner. You know how they sound in parody; what’s shocking is to go back and listen to an actual Elvis record, or the original Star Trek, and compare to the source. At some point impersonations started doing comic exaggerations of one another, with any reference to the original forgotten, and now there’s this thing that is “a William Shatner impersonation” that hasn’t got anything to do with the source. Of course, since it communicates, and entertains, and amuses, it’s serving some purpose, but it’s still, really, a weird phenomenon.