Ha, I used to be like that too. I was so scared because I thought I'd cut up something important.
And then by the end, I ended up just sort of randomly cutting things up to see what it was. We actually tore up the diaphragm of our cat...unintentional, obviously.
And you wish your cat had a tumor. And he had a hole in his stomach, and a bunch of fat and small intestines were hanging out. Plus they chopped off the tail. And we could see poop coming out. (I like to keep people well informed :] )