I want to talk about tempering

[LineageRazor]

One thing that I'm curious about, is whether Aether drained by Primals regenerates over time, or if it's gone forever. Aether seems to be tied to Hyaedalyn in an intimate way; she is weakened when Aether is abused, which is very likely why Ascians are so gung-ho on Primal summoning. Presuming that the summonings were to stop, though, would Hyaedalyn eventually recover, and return Aether to the world (including Aether-drained areas like the Burn), or is her current diminished state a permanent thing?

If Aether can be restored over time, perhaps the existence of a single Primal would not be that big a deal. That could be the rationale behind Ifrit's and Garuda's insistence on other summons being heretical - as long as they're the only one on the block, Hydaelyn can handle the strain, and they get to promote their agenda without worry of long-term harm coming to the planet via Aether drain.

The existence of the Burn might imply that lost Aether is a permanent change - but, on the other hand, the Burn was a pretty extreme case, and may simply take a long time to heal - time the Ascians are not allowing her, with their continued harassment.

[Eisenhower]

One thing that I'm curious about, is whether Aether drained by Primals regenerates over time, or if it's gone forever.

It could be that aether once committed to a primal becomes incompatible with Hydaelyn. In such a case, the aether could very well disperse and exist but still deny Hydaelyn power. If the Ascian-derived summoning methods were part next-level plotting, it may also be the case that such dispersed aether remains compatible with Zodiark, should it (he?) ever need the aether.

[LineageRazor]

Note that both Nael and Lousoix had the grip of the primal relinquished off them, The canonicity of that might be questionable but I believe that the effect of tempering can be removed

I think that in Nael's case, at least, it was explicitly stated that Bahamut relinquished his hold on Nael because Nael had died and was no longer of use to him. The "untempered" Nael we witnessed was basically Nael's ghost, just prior to dispersing into the Lifestream. It is certainly possible that tempering ends with an individual's death, in all cases - though if they desire, a sufficiently powerful Primal can choose to hold onto the soul after death and construct a new body for it (again, as was the case with Nael). There's no point in holding onto a disembodied soul with no body, though, so Primals generally don't bother.

I think the primal has to be currently existent to maintain tempering after death, though.

It could be that aether once committed to a primal becomes incompatible with Hydaelyn. In such a case, the aether could very well disperse and exist but still deny Hydaelyn power. If the Ascian-derived summoning methods were part next-level plotting, it may also be the case that such dispersed aether remains compatible with Zodiark, should it (he?) ever need the aether.

I like this theory, and it makes a lot of sense. Primals act as a kind of "converter", changing Hydaelyn-aether into Zodiark-aether. The biggest flaw I see with it, though, is that Ascians seem just as gung-ho on defeating Primals as they are on summoning them. Wouldn't it make more sense for them to promote keeping the Primals around as long as possible to process as much aether as possible before they're destroyed? In ARR, the Ascians were clearly enthusiastic about the WoL defeating Primals, all part of their mysterious plan...

Maybe the act of summoning converts a lot more aether than is converted by the primal just passively existing? In that case, a cycle of repeatedly summoning and destroying a primal would make sense under this theory.