I agree it's an exercise in futility to sweat over what to do with bad reviews. Fortunately for me, the ratio of good ones far outweighs the bad, but it still stings. Commenting on a bad review just makes the author look childish and defensive IMHO. I have also found that most of my one star reviews have a scathing, almost personal bite to them - like they
know me and/or might be one of the pathetic characters in my books. If that's the case, then

BTW, each time I get a horrible review, my sales go through the roof. Go figure.