This somehow always reminds me of video games. Press <whatever> to hold your breath and your accuracy increases, your aim is more steady.

Anecdotally I think there is some truth to this; hypoxia might lead to greater accuracy and better decisions.

I've had this thought for years and I don't know what I'm talking about just so you know.

"Hold your breath" does have some legs and seems to be quite a common theme especially when dealing with situations which require immense concentration.