If time spent fixing bugs and revising text doesn’t count as part of the four-hour limit, then you can spend any amount of time improving your game, right? That hardly seems to be in the spirit of the speedy nature of La Petite Mort.
If you’re talking about time spent literally testing, meaning the game is being played by other people and you’re waiting for them to give you feedback so you can make revisions, then I’d say that’s not “time spent writing words or code” and I wouldn’t count it. But having somebody test your game so you can revise it based on feedback hardly seems to be in the spirit of the speedy nature of La Petite Mort.