>> Who started peddling this idea that the nominee can hire/fire the head of the RNC?
You mean everything I read at Free Republic is not true??!? :-0
It's amazing. People build up in their heads this fantasy of how their preferred candidate is going to have all these magical powers, but they don't actually pay enough attention to try to understand the mechanics of how the power actually works.
A lot of people seem to think that "executive orders" can pretty much do anything, but they can't. They are limited in their effect, which is why Presidents still push for legislation. Even Obama is finding out that some of his executive orders don't have the power he thought they did.