I remember sitting in gym class in high school one day, not long after the song came out, and two or three of us were trying to figure out all the references in it. Well, what else would we be doing in gym class?
I do think that it is interesting that in the Wikipedia article on the song, the possibility is raised that the line "Helter skelter in a summer swelter" is referring to Charlie Manson and the murders in the summer of 1969, and that interpretation never even occurred to us despite the fact that where we sat discussing the song that day was around ten miles from where Charlie and the gang were living when they did those murders and some of us knew people who had hung out up there on occasion. Go figure.