This is pretty cool, but there is an assumptions that is wrong and worth highlighting: That musical improvisation is a rare talent, and an unusual mental state. It's certainly a rare state for post-Baroque-era European culture. The musical styles Charles demonstrates have their cultural roots elsewhere. Even in Europe, during the Renaissance and earlier musical improvisation was normal.
So this is something we did to ourselves. We created elaborate polyphonics works, which required printed sheet music and tightly controlled performance. We developed musical theory to amazing new levels, we sought complete freedom in our choice of musical scales. To improvise music with the full expressive potential of the equal tempered scale truly requires genius. It's twelve times harder to improvise to a randomly chosen piece of music than it would be if music only came in one scale. We developed technologies that could record the very best performances, so that this has become the standard against which all musicians are measured, and seeing the hopelessness of competing against this we created a culture that values individuality over skill.
The blue patch on the top of the frontal lobe, the constantly anxious super-ego, the AT Field, the courtier's careful pose and the anxious wish to be worthy of their new status by the nouveau riche, that is the culture we have created.
What we need now is not to learn how to improvise, it is to work out what it is we are doing to our own children that kills their ability to improvise, and stop doing it.