“Brazilian superstar Neymar's brain activity while dancing past opponents is less than 10 percent the level of amateur players, suggesting he plays as if on auto-pilot, according to Japanese neurologists.”
If you are extremely comfortable doing something to the point that you can do so automatically, then actually thinking about it will be much less effective.
There were also a number of bad pilots who functioned as targets; taking so much time and concentration to merely keep the plane in the air that they didn't realize there was a killer behind them.
A popular culture reference shows up in this clip that's pretty good https://www.youtube.com/watch?v=NbecIBvR3mE
I've always thought that this phenomenon is what is being referred to when athletes talk about being in the zone.