Well said... I also think that the way we look at Sarah Palmer in 2018 is very different from the way we looked at her in 1991. We have both Fire Walk With Me + The Missing Pieces both suggesting she had some awareness of what was happening in her house, coupled with a cultural shift in views towards sexual abuse. What was once a helpless bystander, now appears almost guilty by her silence. Even before S3 aired, I couldn't help but look at Sarah and think of abuse cases reported in the media, where institutions and powerful individuals were held accountable for failing to act against a predator among their ranks (Joe Paterno instantly comes to mind).Mr. Reindeer wrote:Whatever the original intentions were, I think it’s highly likely that when L/F rewatched E29 together while writing S3, they formed some new ideas about that moment that may not have had anything to do with whatever DKL was thinking in 1991 when he conceived it. For instance, it seems likely to me that that scene was the germ of the idea that Sarah could be “inhabited” in the new series.
Sarah is obviously a tragic figure, but I think her guilt is ultimately the most tragic thing about her, the fact that she knew but didn't act. I read somewhere that the white horse has been interpreted as her mind's way of blocking out Leland's actions and Laura's pain. "The horse is the white of the eyes, and the dark within" indeed.
But getting back to the phone impostor, I feel like it's most likely Sarah/JUDY, but Cooper (or some version of) makes more sense, thematically anyway. Cooper and Sarah have a strange relationship. I always thought it was odd how he avoided her during the initial investigation of S1/S2. And that scene where he comforts her over Leland's passing seems so odd in hindsight, specifically the way he simultaneously absolves Leland and Sarah of any guilt. It's like Coop is almost complicit in Sarah's denial.