McDonald's: Sort Your Head Out

My friend has told me that his grandfather created the McDouble sandwich a long time ago before McDonalds was called McDonalds. It was much bigger than it is now. That's probably because his boss stole his idea. My friend's grandfather quit because of that. Now he takes care of my friend with the help of his wife where I live. My friend isn't lying to me. In fact, he never has. This is the truth between the buns, covered in a sause of mystery and secrecy. Why is it secret? You're just gonna have to find out yourself.