El Sandwich and Planeo

" I like to think of the sandwich as a form of ‘playing footsie’, as you might with the object of your affection under a dining table at a dinner party. I have always fantasised that the original purpose of this gesture was to test out the response of the lady in your arms while in the thicket of the dance floor. The benefit would have been that, if she was under the critical scrutiny of her chaperone (perhaps a beefy brother), he would not be able to see that you were being suggestive. She for her part would have the freedom to respond in kind if she fancied you and ignore it if she did not. "