>At this speed the player is reacting (and hitting with correct timing) about ten notes (arrows) per second. This is possible by memorizing and reacting to group patterns instead of individual notes, but more importantly, reacting unconsciously.

You've just described how people play music in general :P the patterns trigger memory and other internal processes (whether it's recalling verbatim or dynamically based on a new pattern from some combination of scales), this escapes the limitation of input output response time because it's all internal with some arbitrary output delay which we account for by "leading" whatever the physical action is (for an exaggeration think about percussion instruments).

If you are at all musical it's fun to do a bit of introspection here... with anything slightly complicated where you do not have time to think about the position of each note (a pretty unnatural way to perform) you will realise that your fingers (or toes in some strange cases), react to a sort of stream of signals internally... it's probably not even a stream but more of a parallel matching against the pattern from which you pick a stream of notes internally because this is right brain stuff.

Disclaimer: i'm not a neuroscientists or musicologists, I just like thinking about the brain and am slightly musical.