Your question: How important do you think speed and ease of recognising and locating the notes is in an alternative notation?
My answer: Music is an aural skill, not a visual skill.
While I once embraced AN to facilitate reading sheet music for playing the keyboard, I am coming to believe that a student would be better served by learning "ear-hand" coordination rather than "eye-hand." That is, first learn to play the way we learn to sing,
"by ear."
(When my children were taught violin, they first learned to play songs by rote, and could play several melodies and rhythms before ever encountering sheet music. My father had learned the traditional way, but by the time I knew him, he only played "by ear",
and could reproduce any melody he heard.)
I discovered, quite by accident, that after spending a year playing only in the key of C, i.e. on the white keys, I could play simple melodies without looking at either music or the keys. And that was on the traditional piano.
I would imagine it would be much more effective on an isomorphic instrument, besides being applicable to any key. Regrettably, "affordable" isomorphic keyboards are not readily available, or have turned out to be of poor quality and durability. I would think the
goals of music education would be better served by creating more isomorphic instruments than by creating more isomorphic notations. [For example, it should be relatively trivial to re-engineer Orff-style xylophones into Janko arrangement, as
Roy Pertchik has done.]
While I admire your ExpressStave notation for its isomorphism, I think the object of "recognizing and locating the notes" would be even better served by a notation that was isomorphic to the instrument, such as Klavarskribo. My own experiments, e.g. ChromaTonnetz,
always combined an isomorphic "shape-note" notehead notation ("isomorphic" for singers) with a "piano-morphic" staff.
At the more advanced level of playing, the student would be recognizing "shapes" rather than notes. At this point, perhaps the notational emphasis should shift to recognizing harmonic intervals, e.g. Pertchik's tri-color notation.
Of course, this is just one man's opinion, and only an amateur musician at that. Regrettably, since retiring from academia, I am no longer in a position to test my hypotheses experimentally.
Joe Austin aka DrTechDaddy
"Music is poetry,
Why print is as prose?"