I think that's the basis of a great story: a very simple plot that lets the storyteller improvise as he/she goes along. I haven't found as many of those as I'd like, but I've had fun with them. You can tell the story over and over again, and never tell the same story.
But Erv told the story the same way every time, almost word-for-word. After five years, I almost had it memorized - but it didn't really "work" for me, so I never told it. But I'd sure like to hear Erv tell it one more time.
-Joe-