The book says him and the healer agree on them: not sure if he came up with the idea but they got his support.

Interesting, the next generation got a more rational form: Fred+George's lockpicking is a great idea, not just for underage magic reasons but because you suspect wizards would cast complex locking charms on things to protect from Aloharama but not actually make the lock itself very secure from a mundane angle. Which has parallels to the sadly rare RPGs that allow you to get round complicated locks that frustrate you rogue by smashing the chest to pieces with a two-handed hammer.