I understand your point but I don't really buy it. I train lifeguards as a hobby/side-job (I'm in uni right now) and pressure is the number 1 reason they give us for failing their final pratical test. I can't give a kid a permit to work as a lifeguard if the pressure of an exam makes him screw up because the real life pressure of saving somebody's life is even greater.
The exact same applies here for all jobs where you expect the engineer to work in stressful situations.