Tempering? (Spoilers)

[EaraGrace]

I think it's stated that Allagans were wrong about which aspect is "stagnation" and which is "stimulation". That misunderstanding is one of the core reasons that nobody made any further progress on curing tempering: they were doing the opposite of what they should have, due to the Allagans' error.

Right, my point was more speculating on a solution to the apparent contradiction of having an astral being temper someone by shifting their aether towards umbral. I couldn’t help but wonder if it was possible to go the other way and still temper someone.