Let's say that the tune is mostly in Aeolian mode. I found that I keep forgetting the changes because when I think V
it is not a chord I used to associate with this number and I find myself 'translating' it to Ionian-based numbering (so I mind-map it as III
chord; Phrygian collection).
In literature you can find explicit numberings for each possible mode, so that I
may mean Aeolian, Phrygian collection etc. depending on mode. I'm an amateur and I have never seen an explanation why they are using so much space to show stuff that can be easily derived or what should I do with it (except memorizing). I always assumed it there is to help in sight reading.
Having run into this problem, should I unlearn to auto-associate say, V
with Mixolydian collection or Dominant function? Is it customary to think of II-V-I
changes as anything else if they are diatonic to given mode and not harmonic cadences with obvious dominant function of V
?
How can I memorize tunes if I don't see obvious patterns, cadences, not many key changes etc.?