I don't personally believe in backtracking/backmasking, at least when it comes to MJ songs. I don't believe that someone like Michael would think, when writing or singing songs, how they would sound backwards. I mean, you'd have to start with the backwards version (the "hidden" message) and then create a "forward" version that gives rise to that - and that's very, very hard. Not only would you have to write specific words (the songwriting process), but you'd also have to sing in a very specific way... The logistics are really quite complicated.