That snaps a few pieces of the puzzle into place; it helps, even if the picture they make is anything but pretty. If that's what they were trying to do...well, there are a few ways to find out, but only one open to him at the moment. "Is that what they were tryin' to do?" It's a loaded question, but J's voice is still quiet and calm. Repairing Sans' tune is taking time, but at least it's working. Small favors.