[Katara nods, thoughtful, noticing the strain in Asami's smile but... again, leaving it alone, for now. Hopefully going in a different direction will be sufficient.]

I'm not sure I understand something. You said that Korra and someone else discovered that Amon was closing off bending with bloodbending. But how did that happen?

[If Tarrlok was the only other bloodbender and Amon had taken his bending away...]

Did that have something to do with Tarrlok as well?