This is one of the best posts I've ever read on this forum! I love your perceptive insight and analysis of these two teams. And I think you're absolutely right. Few have explained so well the source of Meryl & Charlie's strength as a team.
I agree their connection is cerebral/soulful. Ultimately, I feel it flows directly from the music. Whatever is in the music, they distill and express outward again through movement, rather purely. The emphasis is on the expression of shared emotion, more than on the "performance" as an entity of its own, separate from the music.
Loving people's thoughts on this. Yes ITA with the "expression of shared emotion."
Mr. P said what he likes about Meryl and Charlie is that regardless of the music Meryl and Charlie perform it in a way that is compelling. He watched the NHK FD on YouTube and he said while he did not care for the Norte Dame music, the way Meryl and Charlie danced to that music is what drove him to watch it until the end.