Board Thread:Naruto Discussions/@comment-25516007-20141008201906/@comment-26302001-20141016004640

Konan knew he had a 5 minute time limit on it, she most likely shared that with Nagato. Also as much of a genius as Itachi is and as fast as he is.. just like Minato he would find a way to hurt Obito and eventually kill him. Obito wouldn't mess with them because he knew it would result in his death.