This is just my reading of Ray Wise's performance in FWWM, but his few showings of remorse or sympathy in FWWM always struck me as being just that: shows, deliberately put on by Leland to convince himself and the world that he was a good guy. There's a scene directly after the fingernail scene, where Leland sits up in his bedroom with a scowl, and the way his face slowly shifts from hateful resolve to sad remorse, it's like watching the wheels turning in the mind of a sociopath in real time. It feels less like his emotion is organically shifting from rage to remorse and more like an angry man forcing his face to look different so what's inside can avoid detection.
But that's just my read -- obviously we can also look at it as straight up possession by BOB. I just think it's so interesting the way FWWM muddies the waters of Leland's motivations, especially when considering how different the concept of BOB functions with Mr. C in S3, not as an occupying demon but rather some giant, cackling gallstone that imbues corrupt men with vague super powers.
I 100% disagree with that, actually, and had never even looked at it that way, but I do find it interesting. And that is the exact post-fingernail scene I was talking about. That looks like a man who is suddenly aware of his actions. He doesn't want to be that way, but that is the way he is, and it's not something one can easily fight. And I'm not saying it signifies possession, although it could. Rather, I am specifically saying that someone like that can experience a moment of clarity like that. Any person who gets so trapped inside their own head/rage can have a moment like that. Sadly, I recognize it from experience, and his shift from rage to remorse is a feeling that I've encountered many times. You ride high, you get trapped in some emotion that won't let go and dig yourself deeper and deeper, you can't help yourself, and then suddenly it hits you and you want to be the kindest and most genuinely sorrowful person in the world. The way it's filmed lends itself to multiple interpretations, as it must do since Leland is in fact possessed. But I think a person who can't help themselves might as well be possessed, which I see as a major facet of both the series and FWWM's portrayal of Leland once you removal the actual supernatural element. And that's not an excuse...it's just the way it is for some people. It's like they're not themselves, literally out of control. Some of those people never feel remorse, but some do. And when Leland goes into Laura's room and tells her how much he loves her, it's a heartbreakingly emotional moment that rings true for me. It's always seemed real, much like many of Lynch's greatest emotional scenes, and I never read it as an act of manipulation by a sociopath.