that clue i obsolete, holding your breath is extremely important if you are shooting something like a sniper rifel to avoid gun sway.
you didnt think of that, but i just did
Actually, I did think of that. In fact, it's one of the most vital clues in the mystery. The immediate assumption is that holding your breath relates to steadying a firearm. In this case, it was to launch a dart from a blowgun. It's a clue that you probably didn't even catch, not because it was obsolete, but because it was subtle.