Keyboard latency
I&#x27;m surprised the &quot;humans don&#x27;t notice 100 ms&quot; argument is even made.  That&#x27;s trivially debunkable with a simple blind A&#x2F;B test at the command line using `sleep 0.1` with and without `sleep` aliased to `true`.  To my eyes, the delay is obvious at 100 ms, noticeable at 50 ms, barely perceptible at 20 ms, and unnoticeable at 10 ms.<p>Not to mention that 100 ms is musically a 16th note at 150 bpm.  Being off by a 16th note even at that speed is – especially for percussive instruments – <i>obvious</i>.<p>On the other hand, if you told me to strike a key less than 100 ms <i>after</i> some visual stimuli, I&#x27;m sure I <i>couldn&#x27;t</i> do it – <i>that&#x27;s</i> what &quot;reaction time&quot; is.