Two is not too few for me. Dirty dishes (quick clean before loading) can be a good long time in the dishwasher if you are healthy at least...They say on average people use less water with dishwashers, assuming full load etc. than by hand, but the extremely cautious would probably use less by hand. Whatever works, but all else being equal, no current drought etc., people should not feel they should not use a dishwasher until a magic number of people uses it. mg