Yep, this is essentially the crux of the matter.
With the exception of pre-alpha materials, every time I've assumed that there was a hole or a contradiction on a large issue, I've been wrong to a certain degree. On occasion we'll have a slight discrepancy which is immediately fixed, but more often than not what is happening is that we were never given a small, but crucial, piece of information - the center puzzle piece that all those around it lock into - the canonical hub, so to speak.
I believe that the rules surrounding the echo are well known and consistently followed, but that we're left with character's interpretations of its limits and thus we ourselves are subject to the same errors they might make in assumption.
For instance, we assumed that Damelliot was a contradiction because we seem to alter his past; in reality, I think it makes far more sense that he himself is using the echo (remember, he passes out at random a lot... as did your character before someone finally diagnosed his blackouts as echo!). Reinterpreted through this lens, the story plays out a lot differently (though I'll work on that once I finish Limsa).
Another example is in the THM storyline, where you use the echo on a rogue THM student. In this echo, you see that in the past they saw a shadow and wondered who it was when in the present they finally realize that it was you... who are entering the echo for the first time. Notice the paradox?
This could be interpreted many ways:
Did we actually enter the past and thus create the time loop we often see in fiction?
Did we link minds and re-create the scene, but play it out different in real time without affecting the true history?
Did we see the true history but the characters misinterpret the meaning and how it happened as a result of the echoer / echoee relationship?
SE knows, I'm sure.
But to make it more tangible for you - our questions become
(A) When we echo, are we physically entering the past, are we seeing an instant replay of the past, or are we entering a real-time re-creation of the scene to explore in new ways?
(B) What are the exact limits of this power?
and, just because I'm still stuck waist deep in Lominsan convoluted-ness
(C) What in the seven hells is Y'shtola doing that she's able to jump around and make copies of herself and escape dangerous situations completely unharmed and none the worse for wear?
I stay out of that thread due to some of the pictures being NSFW, and I'm usually only in the forums while at work.
Never played that game.
I'm doing a bit of head scratching for the rest of your post... you say:
But then you say:
Wouldn't leaving a strong enough impression change the past then? at least for that person?
And then you say:
But you already said that you Echo jump as yourself O_o
I am by no means trying to defend my theory, just looking for clarification so I don't feel so nubtastic reading what you posted.
I'm still editing my original post and revising (I tend to write scatterbrained then rearrange later).
I'll address those points later, but first check out what I've revised it to.
Provided everything you said is true - perhaps you can give me some assistance on figuring out the Lominsan storyline - particularly how Hob taking you to the 'Cuda's "sequester ship" could trigger an echo of Emerick being freed, Y'shtola showing up talking about Ascians, Travanchet attacking the sequestered fleet, and the Sea Serpent tidal waving everything into oblivion. Is it even Hob doing it!?
Also, still rabid about how Y'shtola even made it off of that situation unscathed and not even bring it up. She has some superpowers... (that telekinetic bullet stop, making copies of herself to surround you, surviving tidal wave, etc.)
She as the same powers as Neo, she uses Kage Bunshin no Jutsu, and she's a water-type Pokemon.
Now I wish I didn't delete all my cutscenes out of frustration (couldn't find right compressions settings and needed the space). I'll probably check it out later on Youtube and maybe some transcripts from wiki sites.
Also, for now I'm pretty much satisfied with my current revision of my post. Might tweak it later.
What's the exact moment the "woosh" happens? (If there is one). If it is Hob doing it, he doesn't have to be exactly nearby, probably just in close enough "range" that you're still able to be in the virtual past. Maybe he was on a ship that was fighting the Sahagin. (Ferne mentions how the CG Midlander is still in Echo during the Battle at Silvertear Falls despite being whisked away because the Party Members could see it happening from a distance).