I always heard it with the following end:
Newbie yells out #, no one laughs. When asked why, Reg shrugs and says "Some people just can't tell a joke."
Incidentily, I told this joke to a 4 year old and a 7 year old. neither of them understood it.
They also didn't get the long-in-the-tooth when I heard it "Where does the Lone Ranger take his garbage? To the dump, to the dump etc" joke.
This generation may in fact be able to hear the wm. Tell overture without thinking of the Lone Ranger. Of course, now when I hear it, I think of that scene in Clockwork Orange...
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