pedanterrific comments on Harry Potter and the Methods of Rationality discussion thread, part 10

[pedanterrific]

Perhaps, for instance, he can detect the approximate magical strength of a person regardless of their appearance?

Yep:

“I know,” said the old wizard. “My apologies, Amelia.” He sighed. “Some of the more recent prisoners had scraps of their magic left, when I looked upon them, but I sensed no uneaten power; the strongest had only as much magic left as a first-year child.