Why is remembering materials from your undergrad degree the meter of "how smart am I?" What a strangely arbitrary scale. > Do you ever feel “slow”? Very often

Why is remembering materials from your undergrad degree the meter of "how smart am I?" What a strangely arbitrary scale. > Do you ever feel “slow”? Very often. I wake up, and feel as if I haven't slept at all. During those times, my memory literally fails me. The other day, I couldn't remember the term "thin provisioning," about which I was drilling a current coworker a few months ago at an interview. So though the concept is trivial to me, I just couldn't find the words to describe it. And yet, even in that state, I sit down, and code, debug issues, write code... I still get my shit done. I spend less time in the kitchen talking to coworkers, though. A better question is, why do you feel you shouldn't feel "slow"? What should make you feel "fast" that you've acquired during your couple years of studying?