Since Randy Scheunemann was her debate coach in 2008 and is now an advisor to Palin, I would think that she has practice debating to some extent. This is only an assumption but I'm am completely positive that you have no proof that she isn't a more experienced debater.
Sarah has improved in every area necessary to become a great presidential candidate because she is first and foremost a superstar and secondly she has applied herself to improve herself. You could tell by her interview with Chris Wallace on Sunday.
You're making assumptions, but are completely positive I have "no proof". I'm drawing a conclusion based upon the facts at hand. I have no knowledge of, and apparently neither do you, of Palin debating anyone privately, but certainly no one publicly, since her debate with Biden.
So, you're completely positive she's a more experienced debater but can't demonstrate any place she's debated or proffer anyone that has been her debate opponent. I hope you're not a scientist.