"I shouldn't allow you within fifty feet of me if you did," he returns equably.
"Quite possibly," he agrees.
He gives him a mildly exasperated look, and repeats, "It's of no moment if your predictions aren't realized, as long as you can justify them and show your understanding of the processes actually used." Then, because he does understand the question, "Post-graduate students are no longer learning recipes. They're learning to think like brewers safely."
"Of course you are," he returns amiably, deeply amused. "That vindictiveness is outweighed by other factors doesn't mean it doesn't exist, Quin. You've admitted to a grudge against Potter's gang and would like to see their memory outraged--a feeling I'm in entire sympathy with, naturally. If you weren't a vindictive person, you wouldn't merely be uneasy at the thought of participating in an act of wanton pyromania, you'd want to do a purification ritual for the sake of their poor, tarnished souls and the tainted land that had been trammeled with them."