It was a really bad joke. If you've used much Hoppes #9, you've learned that it's a powder solvent and doesn't remove lead or copper very well at all. It also doesn't do much to protect the metal so you've still got to oil the piece after cleaning it. About all I use Hoppes for anymore is to chase the more agressive cleaners if I don't have hot running water to rinse. I also have an ultrasonic cleaner and just use hot soapy water in that as a cleaning fluid.
Of course everyone has their own opinions and YMWV. I've heard that Hoppes works well for injectors but I've also noted that it isn't used on the automotive side of things.