She raised her hands, but as the balefire launched itself, something flashed around her and she jerked. ...
Because she had jerked, the balefire she meant to slice through the cabin and passenger instead had sliced diagonally through the middle of the boat, about where the oarsmen had stood, and the bodyguards. Because the rowers had been burned out of the Pattern before the balefire struck, the two halves of the craft were now a good hundred paces back up the river. Then again, perhaps it was not a complete disaster. Because the slice from the boat's center had gone at the same time the boatmen had died, the river had had minutes to rush in. The two parts of the boat sank out of sight in a great froth of bubbles even as her eyes shifted to them, carrying their passenger to the depths.

Here's a test situation: If you shoot someone with an arrow through the head and then balefire the floor beneath their dead body... Did the floor vanish before the arrow hit them and thus allow them to fall below the arrow's path, meaning they are now alive? I personally do not believe this to be so. The person is still dead with the arrow through their head. If you believe it reverses the victim's fate, then we do indeed view the mechanics of balefire completely differently. Because I don't believe that balefiring the floor, arrow or bow after the event occurred will undo the death, but balefiring the archer would do so.