Which is why, Jack, I added the caveat that I'm not much of a scholar... Inconsistent terminology apropos of modes and keys is rife on harmonica forums, which is why I used all those speech marks.

As it happens, Pseudo, I possess a Hohner Erica D/G. It has at least as many notes on the G row as a G ten-hole harmonica, which is wot I mostly play, ditto for the D row, including missing notes in common at the bottom end. I have only one complete octave in the harmonica. I can retune one note in the bottom octave to give me back the missing sixth for G and A tunes. At least you have the flexibility of notes on crossing rows that I don't have. The guitar men I play with are intelligent enough. If I go out with blues harps in D, G and A I can handle, at a guess, over 90% of Irish tunes. Pesky tunes with accidentals can either be cheated on or notes can be bent. The main exception is Cnat in D tunes. Take Ashokan Farewell for example. Yeah, please take the hateful thing, as far away as possible.