Off topic board for this, bro. Either that or lore board, I'll wait for a mod to decide
Technically then miraak could also wield it if he could somehow get his hands on it. Also I call bullshit on your "Absorbing lifeforce upon touching the hilt" arniel used it a few times to strike the warped soul gem and didnt die of "touching the hilt"
Nah, seeing how Keening worked in the previous games and stuff. It must have lost tonnes of power when the heart was banished. After all, it was made to extract the heart's power. It would have naturally became useless should the heart dissapear.
If Keening extracted the heart's power, does that mean the Keening became more powerful?
or maybe because the dragonborn owes his soul to practically everyone, perhaps keening isn't powerfull enough to touch his sould. As arniel not dying i have no clue
The heart is gone. What would power Keening?
Itself.