I can't think of too many Olympic sporting events where surprise is a variable. And for good reason. People want to see athletes perform at extraordinary levels which they train for.[/QUOTE
Anything where you face human competition on the field of play.
I don't see how not being able to memorize practiced actions for the entire performance ahead of time means you don't see extraordinary levels of performance.
The "you can't keep it hidden somebody will cheat" angle might be the killer though.
Naw. Even in boxing, wrestling, judo, etc. one's competitors are scouted. In the end it would be impossible to keep a course 100% secret so it's a non-starter.