DCStudio, your post set up a host of thoughts and associations. "It would be wonderful if they let us know that counterpoint was played" which reminded me that the theory books I have mostly just shove around notes according to rules. But when I started with theory rudiments, I had already played around with intervals and such, so I associated these things with what I heard. Fortunately the first harmony intro. that I got was old and started with the instruction that we were to learn to hear what we wrote. This It looked different from the Mozart and Beethoven I learned first. brought an association too. I was in choirs, and when I learned to sight read using chorales, I tended to follow the 4 voices horizontally. Later I learned to see it vertically as chords which makes it easier to play in another sense.
As you know, I learned Solfege first. The instruction was not sophisticated back then and it was in a primary grade. I found out later that we actually had a sense of implied harmony in it, even though it involves the melody. Sol also has the feeling of the Dominant. Ti was sung closer than a semitone to the upper Tonic, and had that feeling of sliding into Do. Melodies do suggest an underlying harmony, and chords do suggest melodies that can ride on them.
I found in interesting when I dabbled briefly in First Species counterpoint (Fux) and read about that period. Apparently originally the notion of chords was not there. The folks were interested in being attuned with the divine, and the harmonious intervals were octaves and fifths. I think thirds were accepted a bit later. So when they wanted to add a second voice, they kept the other voice at a distant that gave that pure sound. It is something you feel because a major second doesn't feel like a fifth. When I used to sing with other, I would harmonize by slipping down a third or fifth just in that way. It wasn't a hard transition to do one-on-one counterpoint in that sense. As I understand, the singing came first, and then when they invented notation, they could start getting fancier.
Topic: Contrapunctual writing