Speaking as a primarily coffee free person who drinks really seldom: that is true. I drink only when I had tough day prior and have to work with barely any sleep. It holds me like a superglue, duct tape and bunch of clamps. I drink a cup at around 7am but no late than 10am. I struggle to fall asleep at 10pm on the days I drink it. I still hear my heart beat and even if I'm tired, my brain can't u wind and slow down to the falling asleep speeds.

Being decaf is all'n'cool and I feel great after a long streak of 8h+ sleeps each day. But once in a while I drink a cup and it shows. I can feel it. My wife can feel it. Coworkers probably can see it too. I am a different type of a person once I drink it.

I guess people with high(er) caffeine tolerance are fine. But I can't imagine drinking more than 2 cups a day. It would screw me so much. People at work drink 7 cups a day. Makes me wonder every time how their life is going.