I know the story of "I Am The Walrus", but John also said: "When real music comes to me - the music of the speres, the music that surpasseth understanding - that has nothing to do with me, cause I'm just the channel. The only joy for me is for it to be given to me, and to transcribe it like a medium... those moments are what I live for."
Anyway, I don't know why many people tend to care too much about the actual interpretation of a song, since I believe that any interpretation could be considered as the good one, and anyone can have an own interpretation of a song. I believe that it's more important the listener's interpretation than the writer's one.