Hannah's OCD in season two was clearly a very personal story that Dunham wanted to tell, and small hints had been dropped in earlier episodes, but the immediate severity with which her disorder surfaced was blindsiding. The abruptness made a certain sort of sense—especially to friends and family, mental illness can sometimes feel like it's appearing out of nowhere—but it was clumsily paired with Hannah's sudden reconciliation with Adam. His transformation from brooding and scary oddball (one sex scene with a girlfriend played by Shiri Appleby felt like a borderline assault) to Hannah's tender protector had no logic to it, and gave the subsequent season, in which their relationship grew increasingly tedious, a listless feel.
More so than any other plotline, Tad's closeted homosexuality had been hinted at from the first season when, in the third episode, Hannah's ex-boyfriend Elijah (Andrew Rannells) theorized that Hannah’s father was gay. Over the next few seasons, Tad had always seemed somewhat uncomfortable in his own skin and dissatisfied with where he had ended up in life, and more encouraging of Hannah's aimlessness as a result. His secret fits into his parenting style and relationship with his daughter, then, as opposed to being just a twist for the sake of a twist. Usually Scolari appeared alongside the wonderful Becky Ann Baker as Hannah's more pragmatic mother, Loreen, but this season Tad visited his daughter at Iowa alone, telling her to quit graduate school if she found it unfulfilling. It nicely played into one of the show's better arcs—Hannah leaving Brooklyn yet failing to achieve any spiritual wholeness as a result—and it was terrifically performed by Scolari, who lent Tad an even more haunted quality than usual.
As Scolari told Vulture in an interview published after the episode aired, he was abreast of Tad's plotline from the start of the season, and according to showrunner Jenni Konner, the twist had been discussed from the beginning of the series. This sense of anticipation shows, and Tad’s reveal wasn’t the only part of the story the writers had clearly laid groundwork for much more carefully this season. The Iowa arc, Ray's (Alex Karpovsky) entering local politics, Marnie's trainwreck relationship with musician Desi (Ebon Moss-Bachrach), and Adam's floundering relationship with artist Mimi-Rose (Gillian Jacobs) all felt like rational progressions from the characters' plotlines last year, signaling perhaps a newfound sense of maturity.
Though the internal machinations of a show's writers room are always hard to puzzle out, it's clear that Dunham has taken a bit of a step back in her overall control of the show. She had a writing credit on every episode of the show's first season, and on all but three in the second and third seasons. This year, she is credited to only four out of 10 episodes, and doesn't have a single solo credit, instead writing alongside Konner and executive producer Judd Apatow, whose influence is much more apparent. Apatow has a long and distinguished career in TV writing, and the best shows he worked on (The Larry Sanders Show, Freaks and Geeks, Undeclared) were exemplars of slow-burn plotting and characterization. While Dunham is obviously the most crucial member of the writing staff, and her voice is never far from the script, her reduced role might help explain why the fourth season has felt like more traditional television—and has been all the better for it.