If you watch his demos you'll notice that there's a very distinctive balance between what the average player and the advanced player can pull off.

As for Miss Nakagawa, one of Yamaha's best Jazz Electone players, is not only a demonstrator but a performing artist as well. In fact, most of the Japanese demonstrators are either winners or finalists of the Yamaha Music Festival. Apart from demonstrating and giving concerts they also publish music books (arranged covers and own compostions) which include registration data.
http://riavenclaw.wordpress.com/2009/05/08/mina-nakagawa-performs-at-ps-mall/ (It's in Indonesian but you'll get the picture.)

[This message has been edited by Taike (edited 09-23-2009).]