Y'know, I hadn't really thought too much about Bob feeling like he's failed Harry as a teacher. On the one hand, Bob never got to teach when he was alive (which I'm totally guessing about, because he seriously doesn't look impressed when faced with young!Harry), and so he had to teach Harry with what he could, but on the other hand, I could see him wishing that he was corporeal/mortal because there's times when he needs to give Harry a good whack in the head, or he wants to demonstrate something because Harry's not getting it, or even just to protect Harry from a spell gone wrong. I can see Bob falling back on his master's teaching methods (which would've most likely included an element of "spare the rod, spoil the child"), but having to make do with what he has. I'm already getting an idea or two for later on in the series. :D

And oh yes, Harry would've wanted to make his teacher proud no matter what. He has such a need for someone to care about him and love him (even if it's in a platonic sense) that he'd do anything short of something really bad to get it. *^^*

*cuddles Harry gently*