"Concerning the Hoard" and the Ruin of Doriath

[Voronmirdil]

if (like me) you're inclined to interpret her as a sovereignty goddess of sorts, whose significance to Doriath lay largely in the conferring of authority upon the now-former King. ... Melian couldn't do much for Doriath after Thingol's death, since otherwise her abandoning the realm to its fate sits poorly with me. On the other hand, if the significance of the dragon's curse really was that great, it could provide an alternative explanation.

You've probably already thought of this in mentioning "alternative explanation" so forgive me if I'm mansplaining, but in this new "Hoard" version it is the loss of the Girdle, whether it collapsed or was removed, that set up the circumstances in which Thingol was killed, not, as you note, his death which motivates Melian to remove the Girdle or, more likely, to leave Doriath causing the Girdle to fall.

The dragon-curse caused Thingol to become a different person than he had been and to act in a way - and it must be recognized that it didn't possess him, but merely worked upon proclivities already within him - in which he forfeited the authority that Melian had conferred upon him. We can't know just how pervasive and long-lasting the dragon-curse was, but there's reason to believe that once the dragon-sickness has been contracted that it might be permanent. Having become unworthy of Melian's authority, he was already "dead to her" before he was actually slain and, according to your idea, her purpose in Doriath was ended.

This is really getting speculative, but one reason she didn't take the news of the Ruin and death of Thingol to Beren and Lúthien could have been that she was already gone from Doriath and on her way back to Aman before the Dwarf-host even invaded. Indeed, it could have been her departure that caused the Girdle to fall, not a specific act of removal on her part.

[Voronmirdil]

Overnight I thought of a problem with the dragon-curse theory: "Concening 'The Hoard'" says, "all dragon-hoards were cursed,
and bred in men the dragon-spirit: in possessors an obsession with mere ownership, in others a fierce desire to take the treasure for their own by violence or treachery."

If the dragon-curse was so powerful that it would, as I have posited, have corrupted Thingol/Doriath to the point that it would motivate Melian to leave/remove the Girdle, why did not the recovery of the Nauglamír by Beren corrupt him as well? (We can probably give both Melian and Lúthien a pass on the theory that as Maia/half-Maia they were immune or at least resistant to the curse.) But Beren was just a Man.

I can think of several possible explanations, but would like to hear what you think.

[Eldy]

I enjoy reading your thoughts on this matter, Voronmirdil! I'm a big fan of speculation and syncretistic explanations that draw on various texts and concepts, even though that's an inherently risky endeavor (risky for the purposes of Lore in that it can lead us to non-Tolkienian conclusions; we have much more freedom in the realm of fanfiction). Your take on the dragon-curse and Thingol seems plausible to me. As you note, it's not a form of supernatural possession, but—as with Thorin in The Hobbit (the book version only)—it exacerbates preexisting personality flaws. Thingol has no shortage of those, of course; his attempt at sending Beren to his death is just one example. Interestingly, The Silmarillion notes that by setting the Silmaril as a bride-price, Thingol "wrought the doom of Doriath, and was ensnared within the curse of Mandos" (p. 167). Here we have a similar case of Thingol's awful personality intersecting poorly with curses laid by powerful supernatural beings, to disastrous effect for his kingdom. Beren, at least in my reading, is a much more chill guy most of the time, and thus perhaps less susceptible to the dragon-curse.

[Voronwë the Faithful]

Particularly after he had already died once!