"Who, WHAT are you?" *main story spoilers*

[Tenkuu]

Not per sé. It's more along the lines of speculation that the Blessing is also a means of reinforcing reality, as opposed to the Echo being able to break it down.

Lahabrea and Igeyorhm fuse with the Echo, "the power to break down the barriers of existence." The former attributes their dissolution to the power granted to us by the Blessing. Either the Blessing is capable of reinforcing reality, or we've simply become so freakishly powerful with it turned back "on" we're able to beat down the Ascian Prime until the energy needed to violate Hydaelyn's law can no longer be provided.

That makes a lot of sense. Well put.

I wouldn't presume as much yet. In both versions Y'shtola merely mentions that something is off about the WoDs. It's more along the lines of being something strange as opposed to someone strange - their character would likely not influence their aetherial signature or makeup. What makes the Ascians off in aetherial terms, isn't that they're all a bunch of megalomaniacs devoted wholly to Zodiark's return, it's that their aether is alien compared to anything on Hydaelyn. The same is likely true of the WoDs.

Is it ever actually mentioned anywhere that their aether is alien though? The video explanation I recall us (and the other Scions) being given rather seemed to imply that they were ordinary beings with such a powerful command of the Echo (in the case of the Overlords) that their souls could survive outside of a vessel for a period of time as a result of their being able to move them at will. Whereas we do not fully comprehend the Echo and have no control over it, the Ascians seem to have attained mastery of it and it never seems to adversely affect them, such as with headaches and fainting spells that we still get.

Bahamut was kept physically restrained inside Dalamud. Perhaps Auracite was involved, but not to keep him contained, and it's a moot point anyway since he's gone (story-wise).

Well, you were talking about what the Allagans did so it seemed logical to bring up Bahamut as a prime example. Not that we know much more about the Triad's bindings though, so in that sense it is indeed moot either way.

It's not from a film. That is Giorgio A. Tsukolas, one of the main "theorists" on the History Channel program "Ancient Aliens." Known for his wild hair and even wilder "theories," I am fond of using a certain .gif of him saying "Is such a thing even possible? ... yes it is!" as no matter how outlandish and insane any "theory" anybody comes up with may be, it is always technically possible.

Sounds interesting. The closest thing to that that I've seen would probably be William Shatner's Weird or What series or the Urban Legends TV show. Feel free to correct me if you feel that those shows are nothing like the one you're talking about though.

Given my tendency to develop actual theories based on empirical evidence we're given, I'm not fond of such speculation. I do have some favorite hypotheses, but without any evidence to really back them up generally refrain from doing as Tsukolas does.

Speculation is more idle and can lead to hypotheses, which in turn can lead to theories. I see no harm in either, and speculation can often be more fun if nothing else.