It has that effect on many. It is an experience. When I finished watching it this time, I found I just had to go back and re-watch from where Willard reaches Kurtz's kingdom to the end of the film. The pacing is brilliant, it is real but unreal. I think that Sheen's performance has been underestimated. The best analogy I can come up with is :"In the land of the blind, the one eyed man is king." I have an inherited condition which made me legally blind in one eye. I have no rods in my right eye; I can see amorphous blobs of color. I'm not sure that this condition has helped my understanding.