I have run this checklist ten thousand times, and today I caught my hand moving to the next switch before my eyes had actually confirmed the last one. The discipline is there, I built it over years. The enemy now is not nerves, it is the quiet boredom of the routine flight, the flight where nothing ever goes wrong until the one time it does.
More people experience this than they realize.
You've mastered the discipline, and now the real danger is complacency on the routine days.
If this sounds familiar, the Library can help you find the bigger picture.