Drew, as this being the internet, people say all sorts of things. Whether they are correct or not remains to be seen. I just know what the master armorer told me when I was certified. Dry firing should not damage a Glock. That being said, every gun that leaves the factory is now in a different state of repair and maintenance so someone that uses aftermarket parts, does a .25 cent trigger job or whatever might experience damage when dry firing. Doesn't make it dry firing's fault.
I'm game though....
Former Certified Super Glock fixer