Hahahahaha! This reminds me of when Mark Kermode and Simon Mayo talked to Steven Spielberg about Jaws. They'd argued for ages about whether the shark had some greater metaphorical significance in the film. Simon said it didn't and Mark said it did. Then Spielberg settled the matter (after laughing a lot) saying: "No, the shark is just a shark." So funny.

Despite all this, people can interpret art how they please, regardless of the filmmaker's intent. I personally view Jaws as akin to a ghost story, with the shark coming back to get Quint, due to his part in the crime against nature that was the atomic bomb (that chilling speech about the Indianapolis is so damn eerie).

But in The Godfather, those stairs are just stairs. :)