Survivor works because so many viewers get caught up in second-guessing the players and the producers. Mark Burnett (and now(?) Jiffy) can flop on a challenge or a twist and - guess what? - people talk about it and call even more attention to the show.
Question: Did ANYONE do a dry run on that forgettable dart/arrow/spear challenge from Pearl Islands (or was it All-Stars?) - the one that everyone bombed on? Another: Everyone switches tribes, except Ambuh. And there are the questions about (apparently) rigged challenges, including one that etched Granny-In-Thongs in our collective memories.
My point? Well, I'm wandering afield here. Survivor works because it appears (at a glance) to be played and put together at or about our level. That keeps us thinking along with those who are actually involved in putting together what is, arguably, the first and best-conceived reality show there is.