Adding Vinegar to Dish Soap

I saw a doctor on a Japanese TV show mention you should add a tiny splash of white vinegar to dish soap when washing up. Not only does it give glass items an extra spotless sheen, apparently it will help completely remove any soap residue that might sit on the dishes when you think you've got it all rinsed off, aiding in what you digest in the future. This definitely piqued our interest and we've started doing this. So far so happy.