"The first principal exception to Gamp's Law says you can't transfigure food!"
"Not as such. There in lies the importance of transmutation."
The girl sighed paging through her notes. "But all the literature refers to transmutation as a form of permanent transfiguration; shouldn't the exception still apply?"
"No, transfiguration reconfigures on the macro-scale dealing more with form than function. Meanwhile, transmutation changes on the micro-scale allowing one to by-pass several related limitations."
"Right, thanks Helena, that's much clearer." The ghost nodded. "Now, about that thing?"
"I shall alert you at once."
She smiled.