This is only a problem in this country. In the rest of the civilized world there is etiquette and convention. A waiter can tell whether you are finished eating or just pausing by the way you place your knife and fork. In the better restaurants your plate is never retrieved before everyone else has finished. The convention is this: when your knife and fork touch at the tips and are spread apart at handle, you are pausing. When they are laid parallel and close to eachother you have finished. No questions asked.