It's not as if using keys to cut something is an idea way out of left field. This seems to be a pretty common practice. That it works well enough most of the time is yet another reason folks don't carry knives as much as we may like.
Of course, the boy did have a knife, but may have been too inexperienced/inept to figure out an application for it.
Of course, the boy did have a knife, but may have been too inexperienced/inept to figure out an application for it.