I think it's cos they don't want to get hurt landing on their back. Now how they do it is a different question all together. Ps, awesome video http://www.yout

I think it's cos they don't want to get hurt landing on their back. Now how they do it is a different question all together. Ps, awesome video http://www.youtube.com/watch?feature=player_embedded&v=RtWbpyjJqrU http://www.youtube.com/watch?feature=player_embedded&v=R... , article is pretty useless.