I was listening to Jay Little talk about the game and how he likes to let players toss in ideas about how Threat affects them in a roll. Jay seems to see the dice pool as a very communal thing, which I think is a great sentiment and in practice increases engagement.
I think that description pushing dice being include din the pool and also in the interpretation of the results is paramount. It often devolves into "ok you take two threat" or the application of a setback die, but to me this is when things aren't living up to their potential.
How far do you take this in practice or do you not allow the players to describe threat?