That seems reason enough to do it. Thinking about it out loud: What if we take in both the paper/sheet into mind, next to the letters fondsize and their position. Not just the letters have relative sized, but the poems themselves as well. So you can hit print, and it will have the exact border where you would have to cut it out if its smaller than a4 for example. Subsequently someone could, because the text can just be rendered as an image, offer a service where you can order printer poetry books, with additional styling and whatnot.