Actually, it makes good sense to me. For one, you have 3 octaves in which there is an easy draw breath pattern between D and A [on a C harp] that fits your favored Trad or Celtic music nicely, yes? Also, you don't lose the first C-E-G chord either, right? I'm sure there are other reasons, but these stuck out to me.
Of course, Tim had even more intriguing counterpoints! :-) Interesting... Bobbie
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