There's no subtext in Harry Potter really; it's all magic, anything can happen. Why do I say this? Because it's a magic spell. It's quite nice in a way. There is a real freedom to it.
If you put Willem Dafoe, Liam Neeson and James Woods in a room together, there wouldn't be room for anyone else.
I think we must quote whenever we feel that the allusion is interesting or helpful or amusing.