Originally posted by EarthNug
I think it's purely a coincidence. We only have so many sounds so if you string enough of them together of course you'll be able to make something out of it.
In the case of lines such as the Stairway To Heaven one, I think it's due to an audio version of matrixing. In the same way that we'll recognize shapes in clouds or demonic faces in, say, a flame, we can hear words in backward gibberish.
For example, here's a short snippet of film that I added captions to about a year ago. I don't know what language the guy is singing in, but I captioned it with English words. Cracks me up.
