I'm sure this one comes up a lot.
In social combat, or just regular rolls, how do you keep player knowledge separate from character? That is, if someone is being evasive but also trying to make it not look like they are being deceptive, how do you do that? Saying they're rolling Deceit is somewhat obvious, after all. Heck, in certain situations having a roll at all can be tipping your hand.
For instance, let's say your players go to someone for information on a subject. She knows a lot about it, and would freely provide the information, but the PCs showing up here at all have her a bit rattled for reasons they should not know. Her goal is to just give enough (truthful) information about the subject they're looking for to get rid of them. She's not lying, she just doesn't want them to get suspicious. Rolling Lore modified by Deceit would be tipping your hand since it's normally a subject she wouldn't even need a Lore roll for. The reverse is also true, particularly when you call for an Empathy roll to oppose her.
What do you do in these sort of situations?