they are two differnt worlds.modes are 7 scales from
one scale. positions are the key harp you are playing
to the tune.
But it is the nature of diatonic instruments that a mode change comes with a
key change. The key and the mode are different things, but the walk hand in
hand on diatonic instruments. That's probably the reason that it confuses
some people.
i never play different scales on one
harp.whyy do that when you can pick up another harp.
If you were playing "Soldiers Joy" in the key of D you might play it 1st
position on a D harp because it flows well. If the next tune is "Scarborough
Fair" in the key of D, you'd most likely switch to a C harp to play it in
3rd position. That's a common reason why someone might switch harps even
though they are going to play in the same key, for the mode change, not a
key change. I don't understand what you are trying to say.