The idea of something being a theory and working at the same time doesn't fit any logic at all. If it isn't fact it shouldn't work. The idea that we can get something completely wrong but consistently in practice have it benefit us everyday is so improbable that it is silly. Back than science got things wrong and millions died because of it. Today if we are wrong you would have to assume that by some crazy chance we are wrong but millions live because of it. You people do know that "theoretical" means unproven right? as in theory. I am pretty sure no one wants to go to a hospital where they use unproven theoretical ideas to heal people...this sounds like which craft to me. They use medicine and drugs that have been PROVEN to work.
You can't take the term "practice" and make a argument out of that these days as medical practice is Greek terminology itself even. WTF did they know than? the idea is that science can change and it does but that has slowed to a crawl.
I also learned in school that the world is round. I am pretty ****ing sure that is a fact and not a theory.