YS 233: Fist paragraph after What Happens When You Break The Laws would be unnecessary if it was impossible to do so accidentally.
YS 236: The section after In your game makes no sense whatsoever if unintentionally killing is impossible.
YS 237: In the first paragraph after In your game
I've said this before, and I guess I'll say it again, though I'm not sure what's unclear about the rules concerning this: A *character* can accidentally kill another. A *player* cannot. So, when you as a player get a "taken out" result you can decide that your *character* accidentally (if they weren't meaning to) killed another if this is a reasonable outcome based on what happened. And if your character does something that would reasonably end with someone's death and you wish for them not to, you need to convince the rest of the table that your result is reasonable.
This means that your character can shoot someone several times and they might live. This is possible, and could be reasonable. It isn't reasonable if the player simply wants their character to avoid being a murderer (they probably shouldn't have shot the guy that many times), at least in my opinion. But it'd be reasonable if, for instance, your character *wanted* the person dead and shot them and left them for dead only to find out that they didn't die. There are other scenarios in which this would be reasonable, and I'll leave it up to your imagination. Also, you could have your character *accidentally* kill someone with a stray bullet, spell, or even a deliberate punch that happened to connect to a sensitive place (or hit someone already injured).
The point is that you, as the player, decide when your character makes this mistake. It's true that this puts a lot of power in the hands of the players, but if you don't trust the people you play with, I'd suggest discussing with them what type of game you'd like to be playing in.