Adam D probably what happens, because my players are most comfortable with it, is that I tweak the game to BW-type expectations and always announce and let them always back out. I just do that.
Structurally, TOR is quite a lot more tangled than it looks at first.
In the Combat subsystem, there are no consequences for failing rolls beyond the lost opportunity cost: you only get the one roll when it’s your turn.
In the Encounter system, you run the risk of running Tolerance out.
In the Journeys system, you risk Fatigue and occasionally a Hazard.
And for all the rolls outside of those subsystems, there’s always a BW-style “intent -> task -> failure consequences” discussion. So even within the game itself there’s an expectation set that negotiating is okay.
It’s kind of a mess.