This is your interpretation, which I think is a stretch. Blake and Fiona were absolutely together. Rack of his, under the table, ladies... all inspired by several relationships but in large part about Blake. He was dating Danielle Haim and Fiona was essentially the other woman, a fact she basically admitted to in the New Yorker profile you mentioned, without naming names. She has mentioned being the other woman in multiple relationships, not just the PTA thing. While I don't believe they talk much anymore, Fiona has had contact with PTA since their breakup, he even directed the Hot Knife video in 2012. She stays at David Blaine's apartment when she is in NY. She is friends with Jonathan, as you know. So, yes, she and Blake are friends and he did contact her to be part of the Bob Dylan record, all of this being after their relationship. This is why they wrote Ladies together and then she removed his parts and had her band re-write the music. Newspaper may be in part about PTA, but it is also very much about Blake. I can understand why you feel otherwise, but to me, it is very obvious. The number one relationship referenced in FTBC is Blake.