I just started reading the neuroscience book Incognito, by David Eagleman, and came across the passage below. It reminded me of the feeling that i experienced when i discovered how easy it was for me to play in octaves on a Hayden duet with a mirrored left side in comparison to one with the conventional arrangement:
"To demonstrate the interference of consciousness as a party trick, hand a friend two dry erase markers -- one in each hand -- and ask her to sign her name with her right hand at the same time that she's signing it backward (mirror reversed) with her left hand. She will quickly discover that there is only one way she can do it: by not thinking about it. By excluding conscious interference, her hands can do the complex mirror movements with no problem -- but if she thinks about her actions, the job gets quickly tangled in a bramble of stuttering strokes."
As i've described it before, although the conventional arrangement was easier to think about, the mirrored arrangement was easier for me to do. I ascribed it to some fundamental way my brain worked, but apparently it is a property of human brains in general.
So far as i can see, there is no overall advantage of one left side arrangement over the other in general chord formation (although some specific chords may be easier in one arrangement or the other). As for counter melodies, it seems to me that the mirrored arrangement has an advantage that the dominant left hand fingers are available to play the more common notes. If these two expectations are true, perhaps we should seriously consider adopting the mirrored left side as a standard for future Hayden beginner concertinas, since it does have the inherent advantage for octave playing. (We can already get mirrored left sides as options on intermediate and advanced Haydens.)
Edited by rlgph, 06 March 2018 - 11:59 AM.