Hermione's turtle vs tortoise moment was quite lovely. She reminds me painfully of me in that sense: obsessing over minor problem with exams -- it drives some people up the wall. I did find her boggart reaction to be a little over the top, however. Hmmm.

I cannot quite make sense of why he has not already killed Scabbers/Peter by the time they get there, however. Why was he hiding behind the door? Did he want Harry to witness it?

Harry annoys me a little in this scene, too. He completely ignores the meaning of Sirius only wanting to kill one person -- if he were a death eater, he would not be limited by that. Harry's complete inability to take in and make sense of new information gets to me. I am surprised Hermione did not pick up on it.

Of course, we also get to Lupin's flaw, which may also (depending on how you interpret him) show up in later books. He has not told Dumbledore that Sirius was an animagus, which is really quite a major thing. But I fully empathise with his reasons for doing it. And it all worked out all right in the end, so I forgive him wholeheartedly, but I thought I'd mention it. It also explains why Dumbledore did not have the Shrieking Shack searched. He knew about the house, but did not know Sirius knew. Hmmm.