This is a really good question, Oryx. I am going to give it a lot of thought and I will answer it more fully on my own page. I too think is is worthy of a more expanded piece. As you know I do not think Snape is an admirable teacher, but this borders on a lot of what bothers me the most as to his methods of teaching. Why would anybody, not just a teacher think that the best way to foster trust in another human being think that consistently treating them badly and then actually killing a much loved and trusted authority figure in front of them foster trust? It has to be admitted that whether you admire Snape and think he is the best thing since frozen custard or you take a more ambivalent view of him, this is not the best way to foster trust. wheNowther you like Dumbledore, as I do or dislike him as you do, killing him for whatever reason in front of Harry, is not going to get Harry's trust. And trust is necessary for Snape to pass on the information to Harry about how Harry must go to his death willingly. Snape didn't know that Dumbledore had figured out that Harry would have the option not to die. Snape had to believe that Harry actually would die, so that Harry would believe it and therefore Voldemort would believe it. Fore this scenario to play out Snape had to be the one to pass the all important message on that would lead to the most important thing in the plan the downfall and death of Voldemort. Since trust is all important it does indeed generate the question, why did Snape not try to win Harry's trust? Why did Snape not have a plan in place to get the information to Harry in case of his death? Snape was in danger, well everybody was. Voldemort was a madman and like the clock in Molly's kitchen that pointed to mortal danger for the entire family, a clock for the entire population of Britain would have pointed to mortal danger, for the simple matter Voldemort would kill anybody, anytime he felt like it. No one person was safe, including Snape. Why was there no backup plan in place in case Snape said black instead of white to Voldemort and Voldemort killed him because of that?