I could see that. The first driver seems to be Scarlet Witch's accident, the final driver I would see as Cap driving his Shield into Iron Man, effectively ending the Avengers.
The first driver seems completely separate from Zemo and his plan. It was kind of a rub for me when I was thinking about it. I feel like the Accord stuff plays out mostly in the Relationship Story with the two teams representing Cap and Iron Man. Just like the confrontation with the Mother at the University pulls double duty for Iron Man's personal throughline, and representing the world at large's changing opinion of the Avengers.
The Zemo stuff is played like a mystery, so the storytelling is really light throughout most of the movie.
Black Panther's quest for vengeance feels separate from the Overall Story. Kind of a sub-story. Ross seems to want to control the Avengers, and Zemo wants to destroy them. I think the confusion is that we don't really see what's happening until the big confrontation at the Hydra facility at the end.
All of the throughlines seem to be blended really well which makes objectivity kind of hard. I think all of the subjective stuff is pretty clearly Iron Man and Cap, but there could definitely be a split OS though.
I'd be interested what other people's thoughts are as well.