I'm no techie or egghead, but when I told my choirmaster, who is also a seriously good musician, conductor & adjudicator, that I played melodeon that is tuned to the keys of G & D, his immediate response was that G is called 'the peoples key', as it is the most commonly & easily used key.

Also the orchestra of course tunes to the oboe in G, is this purely coincidental, or do one of you clever bods know a technical reason?

Angela