And here is where you are wrong sir.
On powder skis, I'm going to note that it really doesn't matter that much since the likelihood of your brakes stoping your skis is about nil and you are better off with powder cords.
That being said, My JJs care alright and I can ski groomed terrain with them, so yeah, brakes are a solid idea.
The issue with bending your brakes is that you need to bend them out far enough so that they don't have contact with the edge of your skis. The more you bend them out, the shorter they are when they are released. Also, the more you bend them out, the weaker they become. Also, when you bend them out, it makes them sit differently on your ski. You need to make sure they stay flat and that you don't bend in slightly the wrong direction. There is a lot more that can go wrong than simply buying a proper sized brake.
Or, you could just buy a brake wide enough. Within 15mm wider is a safe spot. The goal is to keep them from dragging. You'd have 7 or less mm hanging off. I've got about 3mm hang off on my JJs mounted standard. So basically, I'd need to be on an insanely steep icy slope (with powder skis) to notice. Unlikely.