To me the thing that constantly validates the theory's "realness" is the intertype relations. A lot of the stuff about functions etc might be wrong but it's pretty cool when you have two people that you've met but they've never met each other, and the moment they meet their behaviour plays out according to formula. It makes you want to grab ahold of them and tell them what's happening, but of course it wouldn't work. In a sense it's like you've gotten (at least some) access to a hidden layer of reality whereas most people just go on like sleepwalkers never suspecting anything...