jedibuttercup

I'd agree with you there.

I'm not sure Harry/John was thinking much about the "destroy themselves" sort of consequences when he dispersed the potion, though; more a desire to knock the arrogance out of them, to picture feet tripping over thresholds, fingers slipping on computer keys, the city randomly going into lockdown, for example. Anything more would be (and was, in the next episode) just bonus.