What he says is, "It's nothing to do with salt, it's to do with metaphor," but beneath the überpatient rephrasing is, are you having a go at me?
"Not really. All that's required is to not serve tea with breakfast. They tend to prefer anything to milk." With the exception, he allows privately, of the ones who can spell osteoporosis. "Ale, I suspect."
His brow crinkles. "Still."
"I don't have to," he says, in the smug tones that mean I have seen someone overreach themselves before they got too high to really hurt themselves on the fall, and it was bloody hilarious. "One of the students achieved a similar effect with polyjuice a few... relative years back."