I didn't say playing the concertina for centuries - I said TUNES rather than chords.
And I am interested in the concertina, and have read A. Anderson's book on it, where, from memory, he mainly instructs folks in playing TUNES, and only briefly, perhaps reluctantly, mentions how to play chords.
Also from memory, on the "Chords in Folk?" thread, you were always agruing for folk accompaniment with chords, were you not..? But I apologise for not knowing that you play the tune sometimes/ on "occasions", and repeat that just the tune, on a concertina, as an accompaniment can sound great, in my opinion.