Well, I'm not sure, but there was a...an incident that happened at Moddey. And Mr Snape was there but he said that Sirius hadn't properly thought about all the ways that the class could have mis-brewed, and he's lucky that Mr Snape was there and had the wherewithal to put cascarilla bark in one of the cauldrons or it would have blown the whole building apart.

And then a few days later he told me to write up regressions for a half a dozen O.W.L. potions and list every possible failure mode for every possible step. He said that it's an essential part of achieving advanced success at potioneering, and that everyone has to prove they can identify the most common problems with loads of potions and that he wants to make sure my education isn't lacking in the fundamentals of potions theory, not just the physical brewing.

So I'm not sure that he'll give it to Sirius but he was certainly influenced by what happened. And in case he does decide to give it to Sirius, I want to make sure it's really well done.

I hadn't actually thought about it in terms of expediency versus pride of ethic, but I think you're right. Of course, sometimes that's an advantage, being willing to do something 'quick and dirty' as Sirius would put it. But mostly I like to be precise, unless it's just too impossible, and then I just try not to let the variance bother me.

No, it won't be easy to get another but if I hadn't given it to them, and they had an emergency, that would have been unforgivable.