This is pretty unexpected, but as I was thinking about grid layouts, I realized all comic books are grid layouts! It makes sense: Little kids read them, so they have to be easy to follow. And they're timeless, so it never looks stale.  It tells the story, and that's what a layout should help do - to facilitate the story.  Your eye just goes from one block to another like reading. The organization doesn't hinder the eye.  The white space between the blocks is similar to that of text boxes or photos in a journalistic layout.  Maybe we now know where magazines got it from? :)