Yes I sort of mentioned it to Machiavel and Rynn that I didn't know why they were so ... bothered about Paisly and neither of them went into as much detail as you did. As Mendicant said, well he'll always be ignorant if his opponents won't offer him their perspective when asked.
The Treaty of the Maroccidens, which I think you have read given you've referenced it before, establishes Chesney, Paisly, and Rettleville as specially vital interests to
all three realms. For practical purposes, any occupation of Paisly, Rettleville, or Chesney is an occupation of Barca, D'Hara,
and Terran. Aurvandil happens to have hit two of those and made threats at the third– you don't win over the Moot by attacking the only three specific regions our founding document identifies as foundational to the existence of our culture.
Regarding realm stats page colors: I do hope people realize that was a joke. Though it is always unsettling to see the Big Blob of White on the dynamic map.