Comment by brokenkebaby

It's guaranteed to be false for the simple fact of human organism adaptability to caffeine. You certainly feel increased alertness after a cup of coffee, so subjectively it may feel very empowering. But if you're a long-time caffeine consumer your baseline (no caffeine alertness) goes down, and in the long run coffee just brings you up to the same level non-consumers have for free. So let's not fool ourselves, coffee is primaryly for pleasure, it doesn't make any miracles for productivity