Oh, you’re right. I got confused about which chapter we were discussing, sorry about that.
That said, something similar applies here: Quirell did 29 charms in Mary’s room, and 30 outside of it. A very simple hypothesis would be that the 30th was something already “implemented” in Mary’s room. (In fact, given that Mary’s room is described as particularly safe even before the charms, the surprising thing is he didn’t do significantly more than 30 charms outside it. The uniqueness of Mary’s room suggests that it would be hard to duplicate it, but it seems strange that nothing could be done to at least approximate it.)
They’re not in Azkaban at the time; this is the discussion in Mary’s Room.
Oh, you’re right. I got confused about which chapter we were discussing, sorry about that.
That said, something similar applies here: Quirell did 29 charms in Mary’s room, and 30 outside of it. A very simple hypothesis would be that the 30th was something already “implemented” in Mary’s room. (In fact, given that Mary’s room is described as particularly safe even before the charms, the surprising thing is he didn’t do significantly more than 30 charms outside it. The uniqueness of Mary’s room suggests that it would be hard to duplicate it, but it seems strange that nothing could be done to at least approximate it.)
But didn’t he do all 30 charms on a previous visit to Mary’s room?
There are too many chapters now for me to track this down easily.