What do you ninjutsu practitioners think about self-defense? There has been some magical shadows floating on ninjutsu,get the point? I´ve often heard that ninjutsu is "rough".I´ve even seen a thread "Is ninjutsu evil?" in budo boards. I have not found any decent information on it´s techniques from web. I´ve heard about unique techniques like to choke opponent with his own blood. What do you think?