That's entirely incorrect. There are no "flaws, ad hoc fixes or initial errors." It is proven beyond any question that the earth is a sphere. And unless you were in school 6,000 years ago, then no, the stuff taught in schools today that the earth is a sphere were not considered "theory." 

Each day's sunrise proves you wrong, you know. As I write this, it's dark in Denver but it's sunny in Honolulu.