I have heard of proprietary ad agency methodologies referred to as "secret sauce."
But when McDonald's starts showing you how to make a Big Mac in your own kitchen (two years ago!) you know the days of secrecy are over:
Why did they do it? McDonald's isn't worried that you could make a cheaper hamburger at home. They know that their customers either don't think they have the time to, can't be bothered, or are on the move. Plus, anyone can get a copycat recipe on the internet. They'd just rather pay someone else to make it, and to provide a trusted result with reliable service. The uniqueness of the product has fallen way down the priority scale.
They also want you to know that their processes and sourcing are transparent and solid.
I guess ad agencies should take note.
