I'm of two minds. One mind, the humane side of me, says that's horrible and no 'lesson' is worth endangering her life. Even if it's 'just' a second floor window, she's going out head-first. The chances of her seriously hurting herself are considerable. That's not teaching her a lesson by giving her a scare, that's risking killing her, crippling her, any number of horrible things.
The other mind, well, wouldn't mind if she landed right on her neck. She's become damn unlikeable in this past arc, and at this stage, I wouldn't be oppossed to her being swiftly moved out of the lime-light in a very final sense. It's a horrible sentiment to have, but she's worked hard to invoke that lately.